[compiler][optim] Add shape for Array.from

(see title)
[compiler] Patch array and argument spread mutability
2025-03-13 11:52:25 -04:00 · 2025-03-13 11:52:25 -04:00
2326 changed files with 33840 additions and 149973 deletions
--- a/.codesandbox/ci.json
+++ b/.codesandbox/ci.json
@@ -1,11 +1,10 @@
 {
-  "packages": ["packages/react", "packages/react-dom", "packages/react-server-dom-webpack", "packages/scheduler"],
+  "packages": ["packages/react", "packages/react-dom", "packages/scheduler"],
  "buildCommand": "download-build-in-codesandbox-ci",
-  "node": "20",
+  "node": "18",
  "publishDirectory": {
    "react": "build/oss-experimental/react",
    "react-dom": "build/oss-experimental/react-dom",
-    "react-server-dom-webpack": "build/oss-experimental/react-server-dom-webpack",
    "scheduler": "build/oss-experimental/scheduler"
  },
  "sandboxes": ["new"],
--- a/.eslintignore
+++ b/.eslintignore
@@ -28,6 +28,3 @@ packages/react-devtools-shared/src/hooks/__tests__/__source__/__untransformed__/
 packages/react-devtools-shell/dist
 packages/react-devtools-timeline/dist
 packages/react-devtools-timeline/static
-
-# Imported third-party Flow types
-flow-typed/
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -468,14 +468,13 @@ module.exports = {
      files: ['packages/react-server-dom-webpack/**/*.js'],
      globals: {
        __webpack_chunk_load__: 'readonly',
-        __webpack_get_script_filename__: 'readonly',
        __webpack_require__: 'readonly',
      },
    },
    {
      files: ['packages/react-server-dom-turbopack/**/*.js'],
      globals: {
-        __turbopack_load_by_url__: 'readonly',
+        __turbopack_load__: 'readonly',
        __turbopack_require__: 'readonly',
      },
    },
@@ -497,7 +496,6 @@ module.exports = {
        'packages/react-devtools-shared/src/devtools/views/**/*.js',
        'packages/react-devtools-shared/src/hook.js',
        'packages/react-devtools-shared/src/backend/console.js',
-        'packages/react-devtools-shared/src/backend/fiber/renderer.js',
        'packages/react-devtools-shared/src/backend/shared/DevToolsComponentStackFrame.js',
        'packages/react-devtools-shared/src/frontend/utils/withPermissionsCheck.js',
      ],
@@ -506,7 +504,6 @@ module.exports = {
        __IS_FIREFOX__: 'readonly',
        __IS_EDGE__: 'readonly',
        __IS_NATIVE__: 'readonly',
-        __IS_INTERNAL_MCP_BUILD__: 'readonly',
        __IS_INTERNAL_VERSION__: 'readonly',
        chrome: 'readonly',
      },
@@ -547,10 +544,13 @@ module.exports = {
  },

  globals: {
+    $Call: 'readonly',
+    $ElementType: 'readonly',
    $Flow$ModuleRef: 'readonly',
    $FlowFixMe: 'readonly',
    $Keys: 'readonly',
    $NonMaybeType: 'readonly',
+    $PropertyType: 'readonly',
    $ReadOnly: 'readonly',
    $ReadOnlyArray: 'readonly',
    $ArrayBufferView: 'readonly',
@@ -559,13 +559,11 @@ module.exports = {
    ConsoleTask: 'readonly', // TOOD: Figure out what the official name of this will be.
    ReturnType: 'readonly',
    AnimationFrameID: 'readonly',
-    WeakRef: 'readonly',
    // For Flow type annotation. Only `BigInt` is valid at runtime.
    bigint: 'readonly',
    BigInt: 'readonly',
    BigInt64Array: 'readonly',
    BigUint64Array: 'readonly',
-    CacheType: 'readonly',
    Class: 'readonly',
    ClientRect: 'readonly',
    CopyInspectedElementPath: 'readonly',
@@ -577,19 +575,15 @@ module.exports = {
    $AsyncIterator: 'readonly',
    Iterator: 'readonly',
    AsyncIterator: 'readonly',
-    IntervalID: 'readonly',
    IteratorResult: 'readonly',
    JSONValue: 'readonly',
    JSResourceReference: 'readonly',
-    mixin$Animatable: 'readonly',
    MouseEventHandler: 'readonly',
-    NavigateEvent: 'readonly',
-    PerformanceMeasureOptions: 'readonly',
    PropagationPhases: 'readonly',
    PropertyDescriptor: 'readonly',
-    PropertyDescriptorMap: 'readonly',
-    Proxy$traps: 'readonly',
+    React$AbstractComponent: 'readonly',
    React$Component: 'readonly',
+    React$ComponentType: 'readonly',
    React$Config: 'readonly',
    React$Context: 'readonly',
    React$Element: 'readonly',
@@ -610,21 +604,17 @@ module.exports = {
    symbol: 'readonly',
    SyntheticEvent: 'readonly',
    SyntheticMouseEvent: 'readonly',
-    SyntheticPointerEvent: 'readonly',
    Thenable: 'readonly',
    TimeoutID: 'readonly',
    WheelEventHandler: 'readonly',
    FinalizationRegistry: 'readonly',
-    Exclude: 'readonly',
    Omit: 'readonly',
    Keyframe: 'readonly',
    PropertyIndexedKeyframes: 'readonly',
    KeyframeAnimationOptions: 'readonly',
    GetAnimationsOptions: 'readonly',
+    Animatable: 'readonly',
    ScrollTimeline: 'readonly',
-    EventListenerOptionsOrUseCapture: 'readonly',
-    FocusOptions: 'readonly',
-    OptionalEffectTiming: 'readonly',

    spyOnDev: 'readonly',
    spyOnDevAndProd: 'readonly',
@@ -642,6 +632,5 @@ module.exports = {
    AsyncLocalStorage: 'readonly',
    async_hooks: 'readonly',
    globalThis: 'readonly',
-    navigation: 'readonly',
  },
 };
--- a/.github/ISSUE_TEMPLATE/19.md
+++ b/.github/ISSUE_TEMPLATE/19.md
@@ -0,0 +1,18 @@
+---
+name: "⚛React 19 beta issue"
+about: Report a issue with React 19 beta.
+title: '[React 19]'
+labels: 'React 19'
+
+---
+
+
+## Summary
+
+<!--
+  Please provide a CodeSandbox (https://codesandbox.io/s/new), a link to a
+  repository on GitHub, or provide a minimal code example that reproduces the
+  problem. You may provide a screenshot of the application if you think it is
+  relevant to your bug report. Here are some tips for providing a minimal
+  example: https://stackoverflow.com/help/mcve.
+-->
--- a/.github/workflows/compiler_discord_notify.yml
+++ b/.github/workflows/compiler_discord_notify.yml
@@ -7,28 +7,9 @@ on:
      - compiler/**
      - .github/workflows/compiler_**.yml

-permissions: {}
-
 jobs:
-  check_access:
-    if: ${{ github.event.pull_request.draft == false }}
-    runs-on: ubuntu-latest
-    outputs:
-      is_member_or_collaborator: ${{ steps.check_is_member_or_collaborator.outputs.is_member_or_collaborator }}
-    steps:
-      - run: echo ${{ github.event.pull_request.author_association }}
-      - name: Check is member or collaborator
-        id: check_is_member_or_collaborator
-        if: ${{ github.event.pull_request.author_association == 'MEMBER' || github.event.pull_request.author_association == 'COLLABORATOR' }}
-        run: echo "is_member_or_collaborator=true" >> "$GITHUB_OUTPUT"
-
  check_maintainer:
-    if: ${{ needs.check_access.outputs.is_member_or_collaborator == 'true' || needs.check_access.outputs.is_member_or_collaborator == true }}
-    needs: [check_access]
    uses: facebook/react/.github/workflows/shared_check_maintainer.yml@main
-    permissions:
-      # Used by check_maintainer
-      contents: read
    with:
      actor: ${{ github.event.pull_request.user.login }}

@@ -38,7 +19,7 @@ jobs:
    runs-on: ubuntu-latest
    steps:
      - name: Discord Webhook Action
-        uses: tsickert/discord-webhook@86dc739f3f165f16dadc5666051c367efa1692f4
+        uses: tsickert/discord-webhook@v6.0.0
        with:
          webhook-url: ${{ secrets.COMPILER_DISCORD_WEBHOOK_URL }}
          embed-author-name: ${{ github.event.pull_request.user.login }}
--- a/.github/workflows/compiler_playground.yml
+++ b/.github/workflows/compiler_playground.yml
@@ -8,8 +8,6 @@ on:
      - compiler/**
      - .github/workflows/compiler_playground.yml

-permissions: {}
-
 concurrency:
  group: ${{ github.workflow }}-${{ github.ref_name }}-${{ github.event.pull_request.number || github.run_id }}
  cancel-in-progress: true
@@ -38,25 +36,10 @@ jobs:
        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: compiler-and-playground-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/**/yarn.lock') }}
+          path: "**/node_modules"
+          key: compiler-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/**/yarn.lock') }}
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-        working-directory: compiler
-      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - name: Check Playwright version
-        id: playwright_version
-        run: echo "playwright_version=$(npm ls @playwright/test | grep @playwright | sed 's/.*@//' | head -1)" >> "$GITHUB_OUTPUT"
-      - name: Cache Playwright Browsers for version ${{ steps.playwright_version.outputs.playwright_version }}
-        id: cache_playwright_browsers
-        uses: actions/cache@v4
-        with:
-          path: ~/.cache/ms-playwright
-          key: playwright-browsers-v6-${{ runner.arch }}-${{ runner.os }}-${{ steps.playwright_version.outputs.playwright_version }}
      - run: npx playwright install --with-deps chromium
-        if: steps.cache_playwright_browsers.outputs.cache-hit != 'true'
      - run: CI=true yarn test
      - run: ls -R test-results
        if: '!cancelled()'
@@ -66,4 +49,3 @@ jobs:
        with:
          name: test-results
          path: compiler/apps/playground/test-results
-          if-no-files-found: ignore
--- a/.github/workflows/compiler_prereleases.yml
+++ b/.github/workflows/compiler_prereleases.yml
@@ -16,19 +16,15 @@ on:
      version_name:
        required: true
        type: string
-      tag_version:
-        required: false
-        type: string
    secrets:
      NPM_TOKEN:
        required: true

-permissions: {}
-
 env:
  TZ: /usr/share/zoneinfo/America/Los_Angeles
  # https://github.com/actions/cache/blob/main/tips-and-workarounds.md#cache-segment-restore-timeout
  SEGMENT_DOWNLOAD_TIMEOUT_MINS: 1
+  GH_TOKEN: ${{ github.token }}
  NPM_TOKEN: ${{ secrets.NPM_TOKEN }}

 defaults:
@@ -50,12 +46,10 @@ jobs:
        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/yarn.lock') }}
+          path: "**/node_modules"
+          key: compiler-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/**/yarn.lock') }}
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
      - name: Publish packages to npm
        run: |
          cp ./scripts/release/ci-npmrc ~/.npmrc
-          scripts/release/publish.js --frfr --ci --versionName=${{ inputs.version_name }} --tag=${{ inputs.dist_tag }} ${{ inputs.tag_version && format('--tagVersion={0}', inputs.tag_version) || '' }}
+          scripts/release/publish.js --frfr --ci --versionName=${{ inputs.version_name }} --tag ${{ inputs.dist_tag }}
--- a/.github/workflows/compiler_prereleases_manual.yml
+++ b/.github/workflows/compiler_prereleases_manual.yml
@@ -14,11 +14,6 @@ on:
      version_name:
        required: true
        type: string
-      tag_version:
-        required: false
-        type: string
-
-permissions: {}

 env:
  TZ: /usr/share/zoneinfo/America/Los_Angeles
@@ -32,6 +27,5 @@ jobs:
      release_channel: ${{ inputs.release_channel }}
      dist_tag: ${{ inputs.dist_tag }}
      version_name: ${{ inputs.version_name }}
-      tag_version: ${{ inputs.tag_version }}
    secrets:
      NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
--- a/.github/workflows/compiler_prereleases_nightly.yml
+++ b/.github/workflows/compiler_prereleases_nightly.yml
@@ -5,8 +5,6 @@ on:
    # At 10 minutes past 16:00 on Mon, Tue, Wed, Thu, and Fri
    - cron: 10 16 * * 1,2,3,4,5

-permissions: {}
-
 env:
  TZ: /usr/share/zoneinfo/America/Los_Angeles

--- a/.github/workflows/compiler_prereleases_weekly.yml
+++ b/.github/workflows/compiler_prereleases_weekly.yml
@@ -0,0 +1,21 @@
+name: (Compiler) Publish Prereleases Weekly
+
+on:
+  schedule:
+    # At 10 minutes past 9:00 on Mon
+    - cron: 10 9 * * 1
+
+env:
+  TZ: /usr/share/zoneinfo/America/Los_Angeles
+
+jobs:
+  publish_prerelease_beta:
+    name: Publish to beta channel
+    uses: facebook/react/.github/workflows/compiler_prereleases.yml@main
+    with:
+      commit_sha: ${{ github.sha }}
+      release_channel: beta
+      dist_tag: beta
+      version_name: '19.0.0'
+    secrets:
+      NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
--- a/.github/workflows/compiler_typescript.yml
+++ b/.github/workflows/compiler_typescript.yml
@@ -8,8 +8,6 @@ on:
      - compiler/**
      - .github/workflows/compiler_typescript.yml

-permissions: {}
-
 concurrency:
  group: ${{ github.workflow }}-${{ github.ref_name }}-${{ github.event.pull_request.number || github.run_id }}
  cancel-in-progress: true
@@ -47,13 +45,10 @@ jobs:
          cache-dependency-path: compiler/yarn.lock
      - name: Restore cached node_modules
        uses: actions/cache@v4
-        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/yarn.lock') }}
+          path: "**/node_modules"
+          key: compiler-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/**/yarn.lock') }}
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
      - run: yarn workspace babel-plugin-react-compiler lint

  # Hardcoded to improve parallelism
@@ -71,11 +66,9 @@ jobs:
        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/yarn.lock') }}
+          path: "**/node_modules"
+          key: compiler-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/**/yarn.lock') }}
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
      - run: yarn workspace babel-plugin-react-compiler jest

  test:
@@ -97,11 +90,9 @@ jobs:
        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/yarn.lock') }}
+          path: "**/node_modules"
+          key: compiler-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('compiler/**/yarn.lock') }}
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
      - run: xvfb-run -a yarn workspace ${{ matrix.workspace_name }} test
        if: runner.os == 'Linux' && matrix.workspace_name == 'react-forgive'
      - run: yarn workspace ${{ matrix.workspace_name }} test
--- a/.github/workflows/devtools_discord_notify.yml
+++ b/.github/workflows/devtools_discord_notify.yml
@@ -1,49 +0,0 @@
-name: (DevTools) Discord Notify
-
-on:
-  pull_request_target:
-    types: [opened, ready_for_review]
-    paths:
-      - packages/react-devtools**
-      - .github/workflows/devtools_**.yml
-
-permissions: {}
-
-jobs:
-  check_access:
-    if: ${{ github.event.pull_request.draft == false }}
-    runs-on: ubuntu-latest
-    outputs:
-      is_member_or_collaborator: ${{ steps.check_is_member_or_collaborator.outputs.is_member_or_collaborator }}
-    steps:
-      - run: echo ${{ github.event.pull_request.author_association }}
-      - name: Check is member or collaborator
-        id: check_is_member_or_collaborator
-        if: ${{ github.event.pull_request.author_association == 'MEMBER' || github.event.pull_request.author_association == 'COLLABORATOR' }}
-        run: echo "is_member_or_collaborator=true" >> "$GITHUB_OUTPUT"
-
-  check_maintainer:
-    if: ${{ needs.check_access.outputs.is_member_or_collaborator == 'true' || needs.check_access.outputs.is_member_or_collaborator == true }}
-    needs: [check_access]
-    uses: facebook/react/.github/workflows/shared_check_maintainer.yml@main
-    permissions:
-      # Used by check_maintainer
-      contents: read
-    with:
-      actor: ${{ github.event.pull_request.user.login }}
-
-  notify:
-    if: ${{ needs.check_maintainer.outputs.is_core_team == 'true' }}
-    needs: check_maintainer
-    runs-on: ubuntu-latest
-    steps:
-      - name: Discord Webhook Action
-        uses: tsickert/discord-webhook@86dc739f3f165f16dadc5666051c367efa1692f4
-        with:
-          webhook-url: ${{ secrets.DEVTOOLS_DISCORD_WEBHOOK_URL }}
-          embed-author-name: ${{ github.event.pull_request.user.login }}
-          embed-author-url: ${{ github.event.pull_request.user.html_url }}
-          embed-author-icon-url: ${{ github.event.pull_request.user.avatar_url }}
-          embed-title: '#${{ github.event.number }} (+${{github.event.pull_request.additions}} -${{github.event.pull_request.deletions}}): ${{ github.event.pull_request.title }}'
-          embed-description: ${{ github.event.pull_request.body }}
-          embed-url: ${{ github.event.pull_request.html_url }}
--- a/.github/workflows/devtools_regression_tests.yml
+++ b/.github/workflows/devtools_regression_tests.yml
@@ -9,8 +9,6 @@ on:
        required: false
        type: string

-permissions: {}
-
 env:
  TZ: /usr/share/zoneinfo/America/Los_Angeles
  # https://github.com/actions/cache/blob/main/tips-and-workarounds.md#cache-segment-restore-timeout
@@ -20,9 +18,6 @@ jobs:
  download_build:
    name: Download base build
    runs-on: ubuntu-latest
-    permissions:
-      # We use github.token to download the build artifact from a previous runtime_build_and_test.yml run
-      actions: read
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-node@v4
@@ -34,15 +29,13 @@ jobs:
        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: runtime-release-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'scripts/release/yarn.lock') }}
+          path: "**/node_modules"
+          key: runtime-release-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'scripts/release/yarn.lock') }}
      - name: Ensure clean build directory
        run: rm -rf build
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn --cwd scripts/release install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
+      - run: yarn install --frozen-lockfile
+        working-directory: scripts/release
      - name: Download react-devtools artifacts for base revision
        run: |
          git fetch origin main
@@ -54,7 +47,6 @@ jobs:
        with:
          name: build
          path: build
-          if-no-files-found: error

  build_devtools_and_process_artifacts:
    name: Build DevTools and process artifacts
@@ -71,13 +63,11 @@ jobs:
        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
      - name: Ensure clean build directory
        run: rm -rf build
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
      - name: Restore archived build
        uses: actions/download-artifact@v4
        with:
@@ -92,21 +82,18 @@ jobs:
        uses: actions/upload-artifact@v4
        with:
          name: react-devtools
-          path: build/devtools
-          if-no-files-found: error
+          path: build/devtools.tgz
      # Simplifies getting the extension for local testing
      - name: Archive chrome extension
        uses: actions/upload-artifact@v4
        with:
          name: react-devtools-chrome-extension
          path: build/devtools/chrome-extension.zip
-          if-no-files-found: error
      - name: Archive firefox extension
        uses: actions/upload-artifact@v4
        with:
          name: react-devtools-firefox-extension
          path: build/devtools/firefox-extension.zip
-          if-no-files-found: error

  run_devtools_tests_for_versions:
    name: Run DevTools tests for versions
@@ -133,11 +120,9 @@ jobs:
        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
      - name: Restore all archived build artifacts
        uses: actions/download-artifact@v4
      - name: Display structure of build
@@ -169,28 +154,17 @@ jobs:
        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
      - name: Restore all archived build artifacts
        uses: actions/download-artifact@v4
      - name: Display structure of build
        run: ls -R build
-      - name: Check Playwright version
-        id: playwright_version
-        run: echo "playwright_version=$(npm ls @playwright/test | grep @playwright | sed 's/.*@//' | head -1)" >> "$GITHUB_OUTPUT"
-      - name: Cache Playwright Browsers for version ${{ steps.playwright_version.outputs.playwright_version }}
-        id: cache_playwright_browsers
-        uses: actions/cache@v4
-        with:
-          path: ~/.cache/ms-playwright
-          key: playwright-browsers-v6-${{ runner.arch }}-${{ runner.os }}-${{ steps.playwright_version.outputs.playwright_version }}
-      - run: npx playwright install --with-deps
-        if: steps.cache_playwright_browsers.outputs.cache-hit != 'true'
-      - run: npx playwright install-deps
-        if: steps.cache_playwright_browsers.outputs.cache-hit == 'true'
+      - name: Playwright install deps
+        run: |
+          npx playwright install
+          sudo npx playwright install-deps
      - run: ./scripts/ci/download_devtools_regression_build.js ${{ matrix.version }}
      - run: ls -R build-regression
      - run: ./scripts/ci/run_devtools_e2e_tests.js ${{ matrix.version }}
@@ -201,5 +175,4 @@ jobs:
      - uses: actions/upload-artifact@v4
        with:
          name: screenshots
-          path: ./tmp/playwright-artifacts
-          if-no-files-found: warn
+          path: ./tmp/screenshots
--- a/.github/workflows/runtime_build_and_test.yml
+++ b/.github/workflows/runtime_build_and_test.yml
@@ -6,14 +6,6 @@ on:
  pull_request:
    paths-ignore:
      - compiler/**
-  workflow_dispatch:
-    inputs:
-      commit_sha:
-        required: false
-        type: string
-        default: ''
-
-permissions: {}

 concurrency:
  group: ${{ github.workflow }}-${{ github.ref_name }}-${{ github.event.pull_request.number || github.run_id }}
@@ -25,95 +17,6 @@ env:
  SEGMENT_DOWNLOAD_TIMEOUT_MINS: 1

 jobs:
-  # ----- NODE_MODULES CACHE -----
-  # Centralize the node_modules cache so it is saved once and each subsequent job only needs to
-  # restore the cache. Prevents race conditions where multiple workflows try to write to the cache.
-  runtime_node_modules_cache:
-    name: Cache Runtime node_modules
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-        with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
-      - name: Check cache hit
-        uses: actions/cache/restore@v4
-        id: node_modules
-        with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          lookup-only: true
-      - uses: actions/setup-node@v4
-        if: steps.node_modules.outputs.cache-hit != 'true'
-        with:
-          node-version-file: '.nvmrc'
-          cache: yarn
-          cache-dependency-path: yarn.lock
-      - name: Warm with old cache
-        if: steps.node_modules.outputs.cache-hit != 'true'
-        uses: actions/cache/restore@v4
-        with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          restore-keys: |
-            runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-node_modules-v6-
-      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - name: Save cache
-        if: steps.node_modules.outputs.cache-hit != 'true'
-        uses: actions/cache/save@v4
-        with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-
-  runtime_compiler_node_modules_cache:
-    name: Cache Runtime, Compiler node_modules
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-        with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
-      - name: Check cache hit
-        uses: actions/cache/restore@v4
-        id: node_modules
-        with:
-          path: |
-            **/node_modules
-          key: runtime-and-compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock') }}
-          lookup-only: true
-      - uses: actions/setup-node@v4
-        if: steps.node_modules.outputs.cache-hit != 'true'
-        with:
-          node-version-file: '.nvmrc'
-          cache: yarn
-          cache-dependency-path: |
-            yarn.lock
-            compiler/yarn.lock
-      - name: Warm with old cache
-        if: steps.node_modules.outputs.cache-hit != 'true'
-        uses: actions/cache/restore@v4
-        with:
-          path: |
-            **/node_modules
-          key: runtime-and-compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock') }}
-          restore-keys: |
-            runtime-and-compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-and-compiler-node_modules-v6-
-      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn --cwd compiler install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - name: Save cache
-        if: steps.node_modules.outputs.cache-hit != 'true'
-        uses: actions/cache/save@v4
-        with:
-          path: |
-            **/node_modules
-          key: runtime-and-compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock') }}
-
  # ----- FLOW -----
  discover_flow_inline_configs:
    name: Discover flow inline configs
@@ -123,7 +26,7 @@ jobs:
    steps:
      - uses: actions/checkout@v4
        with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
      - uses: actions/github-script@v7
        id: set-matrix
        with:
@@ -133,7 +36,7 @@ jobs:

  flow:
    name: Flow check ${{ matrix.flow_inline_config_shortname }}
-    needs: [discover_flow_inline_configs, runtime_node_modules_cache]
+    needs: discover_flow_inline_configs
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
@@ -142,91 +45,76 @@ jobs:
    steps:
      - uses: actions/checkout@v4
        with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
      - uses: actions/setup-node@v4
        with:
          node-version-file: '.nvmrc'
          cache: yarn
          cache-dependency-path: yarn.lock
      - name: Restore cached node_modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          restore-keys: |
-            runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-node_modules-v6-
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
      - name: Ensure clean build directory
        run: rm -rf build
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
      - run: node ./scripts/tasks/flow-ci ${{ matrix.flow_inline_config_shortname }}

  # ----- FIZZ -----
  check_generated_fizz_runtime:
    name: Confirm generated inline Fizz runtime is up to date
-    needs: [runtime_node_modules_cache]
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
      - uses: actions/setup-node@v4
        with:
          node-version-file: '.nvmrc'
          cache: yarn
          cache-dependency-path: yarn.lock
      - name: Restore cached node_modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          restore-keys: |
-            runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-node_modules-v6-
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
      - name: Ensure clean build directory
        run: rm -rf build
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
      - run: |
          yarn generate-inline-fizz-runtime
-          git diff --exit-code || (echo "There was a change to the Fizz runtime. Run \`yarn generate-inline-fizz-runtime\` and check in the result." && false)
+          git diff --quiet || (echo "There was a change to the Fizz runtime. Run `yarn generate-inline-fizz-runtime` and check in the result." && false)

  # ----- FEATURE FLAGS -----
  flags:
    name: Check flags
-    needs: [runtime_node_modules_cache]
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
      - uses: actions/setup-node@v4
        with:
          node-version-file: '.nvmrc'
          cache: yarn
          cache-dependency-path: yarn.lock
      - name: Restore cached node_modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
      - name: Ensure clean build directory
        run: rm -rf build
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
      - run: yarn flags

  # ----- TESTS -----
  test:
    name: yarn test ${{ matrix.params }} (Shard ${{ matrix.shard }})
-    needs: [runtime_compiler_node_modules_cache]
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
@@ -260,106 +148,56 @@ jobs:
    steps:
      - uses: actions/checkout@v4
        with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
      - uses: actions/setup-node@v4
        with:
          node-version-file: '.nvmrc'
          cache: yarn
-          cache-dependency-path: |
-            yarn.lock
-            compiler/yarn.lock
-      - name: Restore cached node_modules
-        uses: actions/cache/restore@v4
-        id: node_modules
-        with:
-          path: |
-            **/node_modules
-          key: runtime-and-compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock') }}
-          restore-keys: |
-            runtime-and-compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-and-compiler-node_modules-v6-
-      - name: Ensure clean build directory
-        run: rm -rf build
-      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn --cwd compiler install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn test ${{ matrix.params }} --ci --shard=${{ matrix.shard }}
-
-  # Hardcoded to improve parallelism
-  test-linter:
-    name: Test eslint-plugin-react-hooks
-    needs: [runtime_compiler_node_modules_cache]
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-      - uses: actions/setup-node@v4
-        with:
-          node-version-file: '.nvmrc'
-          cache: yarn
-          cache-dependency-path:  |
-            yarn.lock
-            compiler/yarn.lock
+          cache-dependency-path: yarn.lock
      - name: Restore cached node_modules
        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: runtime-and-compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock') }}
-      - name: Install runtime dependencies
-        run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - name: Install compiler dependencies
-        run: yarn install --frozen-lockfile
-        working-directory: compiler
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: ./scripts/react-compiler/build-compiler.sh && ./scripts/react-compiler/link-compiler.sh
-      - run: yarn workspace eslint-plugin-react-hooks test
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
+      - name: Ensure clean build directory
+        run: rm -rf build
+      - run: yarn install --frozen-lockfile
+      - run: yarn test ${{ matrix.params }} --ci --shard=${{ matrix.shard }}

  # ----- BUILD -----
  build_and_lint:
    name: yarn build and lint
-    needs: [runtime_compiler_node_modules_cache]
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix:
        # yml is dumb. update the --total arg to yarn build if you change the number of workers
-        worker_id: [0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24]
+        worker_id: [0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19]
        release_channel: [stable, experimental]
    steps:
      - uses: actions/checkout@v4
        with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
      - uses: actions/setup-node@v4
        with:
          node-version-file: '.nvmrc'
          cache: yarn
-          cache-dependency-path: |
-            yarn.lock
-            compiler/yarn.lock
+          cache-dependency-path: yarn.lock
      - uses: actions/setup-java@v4
        with:
          distribution: temurin
          java-version: 11.0.22
      - name: Restore cached node_modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: runtime-and-compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock') }}
-          restore-keys: |
-            runtime-and-compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-and-compiler-node_modules-v6-
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
      - name: Ensure clean build directory
        run: rm -rf build
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn --cwd compiler install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn build --index=${{ matrix.worker_id }} --total=25 --r=${{ matrix.release_channel }} --ci
+      - run: yarn build --index=${{ matrix.worker_id }} --total=20 --r=${{ matrix.release_channel }} --ci
        env:
          CI: github
          RELEASE_CHANNEL: ${{ matrix.release_channel }}
@@ -373,11 +211,10 @@ jobs:
        with:
          name: _build_${{ matrix.worker_id }}_${{ matrix.release_channel }}
          path: build
-          if-no-files-found: error

  test_build:
    name: yarn test-build
-    needs: [build_and_lint, runtime_compiler_node_modules_cache]
+    needs: build_and_lint
    strategy:
      fail-fast: false
      matrix:
@@ -412,44 +249,28 @@ jobs:
          # TODO: Test more persistent configurations?
        ]
        shard:
-          - 1/10
-          - 2/10
-          - 3/10
-          - 4/10
-          - 5/10
-          - 6/10
-          - 7/10
-          - 8/10
-          - 9/10
-          - 10/10
+          - 1/3
+          - 2/3
+          - 3/3
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
      - uses: actions/setup-node@v4
        with:
          node-version-file: '.nvmrc'
          cache: yarn
-          cache-dependency-path: |
-            yarn.lock
-            compiler/yarn.lock
+          cache-dependency-path: yarn.lock
      - name: Restore cached node_modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: runtime-and-compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock') }}
-          restore-keys: |
-            runtime-and-compiler-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-and-compiler-node_modules-v6-
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
      - name: Ensure clean build directory
        run: rm -rf build
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn --cwd compiler install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
      - name: Restore archived build
        uses: actions/download-artifact@v4
        with:
@@ -462,35 +283,26 @@ jobs:

  process_artifacts_combined:
    name: Process artifacts combined
-    needs: [build_and_lint, runtime_node_modules_cache]
-    permissions:
-      # https://github.com/actions/attest-build-provenance
-      id-token: write
-      attestations: write
+    needs: build_and_lint
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
      - uses: actions/setup-node@v4
        with:
          node-version-file: '.nvmrc'
          cache: yarn
          cache-dependency-path: yarn.lock
      - name: Restore cached node_modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          restore-keys: |
-            runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-node_modules-v6-
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
      - name: Ensure clean build directory
        run: rm -rf build
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
      - name: Restore archived build
        uses: actions/download-artifact@v4
        with:
@@ -499,7 +311,7 @@ jobs:
          merge-multiple: true
      - name: Display structure of build
        run: ls -R build
-      - run: echo ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }} >> build/COMMIT_SHA
+      - run: echo ${{ github.sha }} >> build/COMMIT_SHA
      - name: Scrape warning messages
        run: |
          mkdir -p ./build/__test_utils__
@@ -509,53 +321,35 @@ jobs:
        # TODO: Migrate scripts to use `build` directory instead of `build2`
      - run: cp ./build.tgz ./build2.tgz
      - name: Archive build artifacts
-        id: upload_artifacts_combined
        uses: actions/upload-artifact@v4
        with:
          name: artifacts_combined
          path: |
            ./build.tgz
            ./build2.tgz
-          if-no-files-found: error
-      - uses: actions/attest-build-provenance@v2
-        # We don't verify builds generated from pull requests not originating from facebook/react.
-        # However, if the PR lands, the run on `main` will generate the attestation which can then
-        # be used to download a build via scripts/release/download-experimental-build.js.
-        #
-        # Note that this means that scripts/release/download-experimental-build.js must be run with
-        # --no-verify when downloading a build from a fork.
-        if: github.event_name == 'push' && github.ref_name == 'main' || github.event.pull_request.head.repo.full_name == github.repository
-        with:
-          subject-name: artifacts_combined.zip
-          subject-digest: sha256:${{ steps.upload_artifacts_combined.outputs.artifact-digest }}

  check_error_codes:
    name: Search build artifacts for unminified errors
-    needs: [build_and_lint, runtime_node_modules_cache]
+    needs: build_and_lint
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
      - uses: actions/setup-node@v4
        with:
          node-version-file: '.nvmrc'
          cache: yarn
          cache-dependency-path: yarn.lock
      - name: Restore cached node_modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          restore-keys: |
-            runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-node_modules-v6-
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
      - name: Ensure clean build directory
        run: rm -rf build
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
      - name: Restore archived build
        uses: actions/download-artifact@v4
        with:
@@ -567,35 +361,30 @@ jobs:
      - name: Search build artifacts for unminified errors
        run: |
          yarn extract-errors
-          git diff --exit-code || (echo "Found unminified errors. Either update the error codes map or disable error minification for the affected build, if appropriate." && false)
+          git diff --quiet || (echo "Found unminified errors. Either update the error codes map or disable error minification for the affected build, if appropriate." && false)

  check_release_dependencies:
    name: Check release dependencies
-    needs: [build_and_lint, runtime_node_modules_cache]
+    needs: build_and_lint
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
      - uses: actions/setup-node@v4
        with:
          node-version-file: '.nvmrc'
          cache: yarn
          cache-dependency-path: yarn.lock
      - name: Restore cached node_modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          restore-keys: |
-            runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-node_modules-v6-
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
      - name: Ensure clean build directory
        run: rm -rf build
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
      - name: Restore archived build
        uses: actions/download-artifact@v4
        with:
@@ -613,23 +402,22 @@ jobs:
    steps:
      - uses: actions/checkout@v4
        with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
      - uses: actions/setup-node@v4
        with:
          node-version-file: '.nvmrc'
          cache: yarn
          cache-dependency-path: yarn.lock
      - name: Restore cached node_modules
-        uses: actions/cache@v4 # note: this does not reuse centralized cache since it has unique cache key
+        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: fixtures_dom-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'fixtures/dom/yarn.lock') }}
+          path: "**/node_modules"
+          key: fixtures_dom-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
      - name: Ensure clean build directory
        run: rm -rf build
-      - run: yarn --cwd fixtures/dom install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
+      - run: yarn install --frozen-lockfile
+        working-directory: fixtures/dom
      - name: Restore archived build
        uses: actions/download-artifact@v4
        with:
@@ -654,7 +442,7 @@ jobs:
    steps:
      - uses: actions/checkout@v4
        with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
      - uses: actions/setup-node@v4
        with:
          node-version-file: '.nvmrc'
@@ -664,31 +452,14 @@ jobs:
      # That means dependencies of the built packages are not installed.
      # We need to install dependencies of the workroot to fulfill all dependency constraints
      - name: Restore cached node_modules
-        uses: actions/cache@v4 # note: this does not reuse centralized cache since it has unique cache key
+        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: fixtures_flight-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'fixtures/flight/yarn.lock') }}
+          path: "**/node_modules"
+          key: fixtures_flight-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
      - name: Ensure clean build directory
        run: rm -rf build
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn --cwd fixtures/flight install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - name: Check Playwright version
-        id: playwright_version
-        run: echo "playwright_version=$(npm ls @playwright/test | grep @playwright | sed 's/.*@//' | head -1)" >> "$GITHUB_OUTPUT"
-      - name: Cache Playwright Browsers for version ${{ steps.playwright_version.outputs.playwright_version }}
-        id: cache_playwright_browsers
-        uses: actions/cache@v4
-        with:
-          path: ~/.cache/ms-playwright
-          key: playwright-browsers-v6-${{ runner.arch }}-${{ runner.os }}-${{ steps.playwright_version.outputs.playwright_version }}
-      - name: Playwright install deps
-        if: steps.cache_playwright_browsers.outputs.cache-hit != 'true'
-        working-directory: fixtures/flight
-        run: npx playwright install --with-deps chromium
      - name: Restore archived build
        uses: actions/download-artifact@v4
        with:
@@ -697,6 +468,16 @@ jobs:
          merge-multiple: true
      - name: Display structure of build
        run: ls -R build
+      - name: Install fixture dependencies
+        working-directory: fixtures/flight
+        run: |
+          yarn install --frozen-lockfile --cache-folder ~/.cache/yarn
+          if [ $? -ne 0 ]; then
+            yarn install --frozen-lockfile --cache-folder ~/.cache/yarn
+          fi
+      - name: Playwright install deps
+        working-directory: fixtures/flight
+        run: npx playwright install --with-deps chromium
      - name: Run tests
        working-directory: fixtures/flight
        run: yarn test
@@ -708,18 +489,16 @@ jobs:
        with:
          name: flight-playwright-report
          path: fixtures/flight/playwright-report
-          if-no-files-found: warn
      - name: Archive Flight fixture artifacts
        uses: actions/upload-artifact@v4
        with:
          name: flight-test-results
          path: fixtures/flight/test-results
-          if-no-files-found: ignore

  # ----- DEVTOOLS -----
  build_devtools_and_process_artifacts:
    name: Build DevTools and process artifacts
-    needs: [build_and_lint, runtime_node_modules_cache]
+    needs: build_and_lint
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
@@ -728,26 +507,21 @@ jobs:
    steps:
      - uses: actions/checkout@v4
        with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
      - uses: actions/setup-node@v4
        with:
          node-version-file: '.nvmrc'
          cache: yarn
          cache-dependency-path: yarn.lock
      - name: Restore cached node_modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          restore-keys: |
-            runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-node_modules-v6-
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
      - name: Ensure clean build directory
        run: rm -rf build
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
      - name: Restore archived build
        uses: actions/download-artifact@v4
        with:
@@ -765,12 +539,6 @@ jobs:
        with:
          name: react-devtools-${{ matrix.browser }}-extension
          path: build/devtools/${{ matrix.browser }}-extension.zip
-          if-no-files-found: error
-      - name: Archive ${{ matrix.browser }} metadata
-        uses: actions/upload-artifact@v4
-        with:
-          name: react-devtools-${{ matrix.browser }}-metadata
-          path: build/devtools/webpack-stats.*.json

  merge_devtools_artifacts:
    name: Merge DevTools artifacts
@@ -781,112 +549,83 @@ jobs:
        uses: actions/upload-artifact/merge@v4
        with:
          name: react-devtools
-          pattern: react-devtools-*
+          pattern: react-devtools-*-extension

  run_devtools_e2e_tests:
    name: Run DevTools e2e tests
-    needs: [build_and_lint, runtime_node_modules_cache]
+    needs: build_and_lint
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
      - uses: actions/setup-node@v4
        with:
          node-version-file: '.nvmrc'
          cache: yarn
          cache-dependency-path: yarn.lock
      - name: Restore cached node_modules
-        uses: actions/cache/restore@v4
+        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
-          restore-keys: |
-            runtime-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-
-            runtime-node_modules-v6-
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
      - name: Ensure clean build directory
        run: rm -rf build
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
      - name: Restore archived build
        uses: actions/download-artifact@v4
        with:
          pattern: _build_*
          path: build
          merge-multiple: true
-      - name: Check Playwright version
-        id: playwright_version
-        run: echo "playwright_version=$(npm ls @playwright/test | grep @playwright | sed 's/.*@//' | head -1)" >> "$GITHUB_OUTPUT"
-      - name: Cache Playwright Browsers for version ${{ steps.playwright_version.outputs.playwright_version }}
-        id: cache_playwright_browsers
-        uses: actions/cache@v4
-        with:
-          path: ~/.cache/ms-playwright
-          key: playwright-browsers-v6-${{ runner.arch }}-${{ runner.os }}-${{ steps.playwright_version.outputs.playwright_version }}
-      - name: Playwright install deps
-        if: steps.cache_playwright_browsers.outputs.cache-hit != 'true'
-        run: npx playwright install --with-deps chromium
+      - run: |
+          npx playwright install
+          sudo npx playwright install-deps
      - run: ./scripts/ci/run_devtools_e2e_tests.js
        env:
          RELEASE_CHANNEL: experimental
-      - name: Archive Playwright report
-        uses: actions/upload-artifact@v4
-        with:
-          name: devtools-playwright-artifacts
-          path: tmp/playwright-artifacts
-          if-no-files-found: warn

  # ----- SIZEBOT -----
  sizebot:
    if: ${{ github.event_name == 'pull_request' && github.ref_name != 'main' && github.event.pull_request.base.ref == 'main' }}
    name: Run sizebot
    needs: [build_and_lint]
-    permissions:
-      # We use github.token to download the build artifact from a previous runtime_build_and_test.yml run
-      actions: read
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
-          ref: ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }}
+          ref: ${{ github.event.pull_request.head.sha || github.sha }}
      - uses: actions/setup-node@v4
        with:
          node-version-file: '.nvmrc'
          cache: yarn
          cache-dependency-path: yarn.lock
      - name: Restore cached node_modules
-        uses: actions/cache@v4 # note: this does not reuse centralized cache since it has unique cache key
+        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: runtime-release-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'scripts/release/yarn.lock') }}
+          path: "**/node_modules"
+          key: runtime-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
      - name: Ensure clean build directory
        run: rm -rf build
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn --cwd scripts/release install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
+        working-directory: scripts/release
      - name: Download artifacts for base revision
-        # The build could have been generated from a fork, so we must download the build without
-        # any verification. This is safe since we only use this for sizebot calculation and the
-        # unverified artifact is not used. Additionally this workflow runs in the pull_request
-        # trigger so only restricted permissions are available.
        run: |
-          GH_TOKEN=${{ github.token }} scripts/release/download-experimental-build.js --commit=$(git rev-parse ${{ github.event.pull_request.base.sha }}) ${{ (github.event.pull_request.head.repo.full_name != github.repository && '--noVerify') || ''}}
+          GH_TOKEN=${{ github.token }} scripts/release/download-experimental-build.js --commit=$(git rev-parse ${{ github.event.pull_request.base.sha }})
          mv ./build ./base-build
+      # TODO: The `download-experimental-build` script copies the npm
+      # packages into the `node_modules` directory. This is a historical
+      # quirk of how the release script works. Let's pretend they
+      # don't exist.
      - name: Delete extraneous files
-        # TODO: The `download-experimental-build` script copies the npm
-        # packages into the `node_modules` directory. This is a historical
-        # quirk of how the release script works. Let's pretend they
-        # don't exist.
        run: rm -rf ./base-build/node_modules
      - name: Display structure of base-build from origin/main
        run: ls -R base-build
      - name: Ensure clean build directory
        run: rm -rf build
+      - run: yarn install --frozen-lockfile
      - name: Restore archived build for PR
        uses: actions/download-artifact@v4
        with:
@@ -899,11 +638,10 @@ jobs:
          node ./scripts/print-warnings/print-warnings.js > build/__test_utils__/ReactAllWarnings.js
      - name: Display structure of build for PR
        run: ls -R build
-      - run: echo ${{ github.event.inputs.commit_sha != '' && github.event.inputs.commit_sha || github.event.pull_request.head.sha || github.sha }} >> build/COMMIT_SHA
+      - run: echo ${{ github.sha }} >> build/COMMIT_SHA
      - run: node ./scripts/tasks/danger
      - name: Archive sizebot results
        uses: actions/upload-artifact@v4
        with:
          name: sizebot-message
          path: sizebot-message.md
-          if-no-files-found: ignore
--- a/.github/workflows/runtime_commit_artifacts.yml
+++ b/.github/workflows/runtime_commit_artifacts.yml
@@ -16,13 +16,6 @@ on:
        required: true
        default: false
        type: boolean
-      dry_run:
-        description: Perform a dry run (run everything except push)
-        required: true
-        default: false
-        type: boolean
-
-permissions: {}

 env:
  TZ: /usr/share/zoneinfo/America/Los_Angeles
@@ -32,40 +25,6 @@ env:
 jobs:
  download_artifacts:
    runs-on: ubuntu-latest
-    permissions:
-      # We use github.token to download the build artifact from a previous runtime_build_and_test.yml run
-      actions: read
-    steps:
-      - uses: actions/checkout@v4
-      - name: Restore cached node_modules
-        uses: actions/cache@v4
-        id: node_modules
-        with:
-          path: |
-            **/node_modules
-          key: runtime-release-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'scripts/release/yarn.lock') }}
-      - name: Ensure clean build directory
-        run: rm -rf build
-      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn --cwd scripts/release install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - name: Download artifacts for base revision
-        run: |
-          GH_TOKEN=${{ github.token }} scripts/release/download-experimental-build.js --commit=${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha }}
-      - name: Display structure of build
-        run: ls -R build
-      - name: Archive build
-        uses: actions/upload-artifact@v4
-        with:
-          name: build
-          path: build/
-          if-no-files-found: error
-
-
-  process_artifacts:
-    runs-on: ubuntu-latest
-    needs: [download_artifacts]
    outputs:
      www_branch_count: ${{ steps.check_branches.outputs.www_branch_count }}
      fbsource_branch_count: ${{ steps.check_branches.outputs.fbsource_branch_count }}
@@ -105,11 +64,27 @@ jobs:
        run: |
          echo "www_branch_count=$(git ls-remote --heads origin "refs/heads/meta-www" | wc -l)" >> "$GITHUB_OUTPUT"
          echo "fbsource_branch_count=$(git ls-remote --heads origin "refs/heads/meta-fbsource" | wc -l)" >> "$GITHUB_OUTPUT"
-      - name: Restore downloaded build
-        uses: actions/download-artifact@v4
+      - uses: actions/setup-node@v4
        with:
-          name: build
-          path: build
+          node-version-file: '.nvmrc'
+          cache: yarn
+          cache-dependency-path: yarn.lock
+      - name: Restore cached node_modules
+        uses: actions/cache@v4
+        id: node_modules
+        with:
+          path: "**/node_modules"
+          key: runtime-release-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'scripts/release/yarn.lock') }}
+      - name: Ensure clean build directory
+        run: rm -rf build
+      - run: yarn install --frozen-lockfile
+        name: yarn install (react)
+      - run: yarn install --frozen-lockfile
+        name: yarn install (scripts/release)
+        working-directory: scripts/release
+      - name: Download artifacts for base revision
+        run: |
+          GH_TOKEN=${{ github.token }} scripts/release/download-experimental-build.js --commit=${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha }}
      - name: Display structure of build
        run: ls -R build
      - name: Strip @license from eslint plugin and react-refresh
@@ -132,10 +107,9 @@ jobs:
          mkdir ./compiled/facebook-www/__test_utils__
          mv build/__test_utils__/ReactAllWarnings.js ./compiled/facebook-www/__test_utils__/ReactAllWarnings.js

-          # Copy eslint-plugin-react-hooks
-          mkdir ./compiled/eslint-plugin-react-hooks
-          cp build/oss-experimental/eslint-plugin-react-hooks/cjs/eslint-plugin-react-hooks.development.js \
-            ./compiled/eslint-plugin-react-hooks/index.js
+          # Move eslint-plugin-react-hooks into facebook-www
+          mv build/oss-experimental/eslint-plugin-react-hooks/cjs/eslint-plugin-react-hooks.development.js \
+            ./compiled/facebook-www/eslint-plugin-react-hooks.js

          # Move unstable_server-external-runtime.js into facebook-www
          mv build/oss-experimental/react-dom/unstable_server-external-runtime.js \
@@ -167,21 +141,15 @@ jobs:
          rm $RENDERER_FOLDER/ReactFabric-{dev,prod,profiling}.js
          rm $RENDERER_FOLDER/ReactNativeRenderer-{dev,prod,profiling}.js

-          # Copy eslint-plugin-react-hooks
-          # NOTE: This is different from www, here we include the full package
-          #       including package.json to include dependencies in fbsource.
-          mkdir "$BASE_FOLDER/tools"
-          cp -r build/oss-experimental/eslint-plugin-react-hooks "$BASE_FOLDER/tools"
-
          # Move React Native version file
          mv build/facebook-react-native/VERSION_NATIVE_FB ./compiled-rn/VERSION_NATIVE_FB

          ls -R ./compiled-rn
      - name: Add REVISION files
        run: |
-          echo ${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha }} >> ./compiled/facebook-www/REVISION
+          echo ${{ github.sha }} >> ./compiled/facebook-www/REVISION
          cp ./compiled/facebook-www/REVISION ./compiled/facebook-www/REVISION_TRANSFORMS
-          echo ${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha }} >> ./compiled-rn/facebook-fbsource/xplat/js/react-native-github/Libraries/Renderer/REVISION
+          echo ${{ github.sha}} >> ./compiled-rn/facebook-fbsource/xplat/js/react-native-github/Libraries/Renderer/REVISION
      - name: "Get current version string"
        id: get_current_version
        run: |
@@ -198,20 +166,15 @@ jobs:
        with:
          name: compiled
          path: compiled/
-          if-no-files-found: error
      - uses: actions/upload-artifact@v4
        with:
          name: compiled-rn
          path: compiled-rn/
-          if-no-files-found: error

  commit_www_artifacts:
-    needs: [download_artifacts, process_artifacts]
-    if: inputs.force == true || (github.ref == 'refs/heads/main' && needs.process_artifacts.outputs.www_branch_count == '0')
+    needs: download_artifacts
+    if: inputs.force == true || (github.ref == 'refs/heads/main' && needs.download_artifacts.outputs.www_branch_count == '0')
    runs-on: ubuntu-latest
-    permissions:
-      # Used to push a commit to builds/facebook-www
-      contents: write
    steps:
      - uses: actions/checkout@v4
        with:
@@ -223,12 +186,12 @@ jobs:
          name: compiled
          path: compiled/
      - name: Revert version changes
-        if: needs.process_artifacts.outputs.last_version_classic != '' && needs.process_artifacts.outputs.last_version_modern != ''
+        if: needs.download_artifacts.outputs.last_version_classic != '' && needs.download_artifacts.outputs.last_version_modern != ''
        env:
-          CURRENT_VERSION_CLASSIC: ${{ needs.process_artifacts.outputs.current_version_classic }}
-          CURRENT_VERSION_MODERN: ${{ needs.process_artifacts.outputs.current_version_modern }}
-          LAST_VERSION_CLASSIC: ${{ needs.process_artifacts.outputs.last_version_classic }}
-          LAST_VERSION_MODERN: ${{ needs.process_artifacts.outputs.last_version_modern }}
+          CURRENT_VERSION_CLASSIC: ${{ needs.download_artifacts.outputs.current_version_classic }}
+          CURRENT_VERSION_MODERN: ${{ needs.download_artifacts.outputs.current_version_modern }}
+          LAST_VERSION_CLASSIC: ${{ needs.download_artifacts.outputs.last_version_classic }}
+          LAST_VERSION_MODERN: ${{ needs.download_artifacts.outputs.last_version_modern }}
        run: |
          echo "Reverting $CURRENT_VERSION_CLASSIC to $LAST_VERSION_CLASSIC"
          grep -rl "$CURRENT_VERSION_CLASSIC" ./compiled || echo "No files found with $CURRENT_VERSION_CLASSIC"
@@ -258,12 +221,12 @@ jobs:
            echo "should_commit=false" >> "$GITHUB_OUTPUT"
          fi
      - name: Re-apply version changes
-        if: inputs.force == true || (steps.check_should_commit.outputs.should_commit == 'true' && needs.process_artifacts.outputs.last_version_classic != '' && needs.process_artifacts.outputs.last_version_modern != '')
+        if: inputs.force == true || (steps.check_should_commit.outputs.should_commit == 'true' && needs.download_artifacts.outputs.last_version_classic != '' && needs.download_artifacts.outputs.last_version_modern != '')
        env:
-          CURRENT_VERSION_CLASSIC: ${{ needs.process_artifacts.outputs.current_version_classic }}
-          CURRENT_VERSION_MODERN: ${{ needs.process_artifacts.outputs.current_version_modern }}
-          LAST_VERSION_CLASSIC: ${{ needs.process_artifacts.outputs.last_version_classic }}
-          LAST_VERSION_MODERN: ${{ needs.process_artifacts.outputs.last_version_modern }}
+          CURRENT_VERSION_CLASSIC: ${{ needs.download_artifacts.outputs.current_version_classic }}
+          CURRENT_VERSION_MODERN: ${{ needs.download_artifacts.outputs.current_version_modern }}
+          LAST_VERSION_CLASSIC: ${{ needs.download_artifacts.outputs.last_version_classic }}
+          LAST_VERSION_MODERN: ${{ needs.download_artifacts.outputs.last_version_modern }}
        run: |
          echo "Re-applying $LAST_VERSION_CLASSIC to $CURRENT_VERSION_CLASSIC"
          grep -rl "$LAST_VERSION_CLASSIC" ./compiled || echo "No files found with $LAST_VERSION_CLASSIC"
@@ -277,31 +240,24 @@ jobs:
      - name: Will commit these changes
        if: inputs.force == true || steps.check_should_commit.outputs.should_commit == 'true'
        run: |
-          git add .
-          git status
-      - name: Check commit message
-        if: inputs.dry_run
-        run: |
-          git fetch origin --quiet
-          git show ${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha }} --no-patch --pretty=format:"%B"
+          echo ":"
+          git status -u
      - name: Commit changes to branch
        if: inputs.force == true || steps.check_should_commit.outputs.should_commit == 'true'
-        run: |
-          git config --global user.email "${{ format('{0}@users.noreply.github.com', github.triggering_actor) }}"
-          git config --global user.name "${{ github.triggering_actor }}"
+        uses: stefanzweifel/git-auto-commit-action@v5
+        with:
+          commit_message: |
+            ${{ github.event.workflow_run.head_commit.message || format('Manual build of {0}', github.event.workflow_run.head_sha || github.sha) }}

-          git fetch origin --quiet
-          git commit -m "$(git show ${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha }} --no-patch --pretty=format:'%B%n%nDiffTrain build for [${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha }}](https://github.com/facebook/react/commit/${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha}})')" || echo "No changes to commit"
-      - name: Push changes to branch
-        if: inputs.dry_run == false && (inputs.force == true || steps.check_should_commit.outputs.should_commit == 'true')
-        run: git push
+            DiffTrain build for [${{ github.event.workflow_run.head_sha || github.sha }}](https://github.com/facebook/react/commit/${{ github.event.workflow_run.head_sha || github.sha }})
+          branch: builds/facebook-www
+          commit_user_name: ${{ github.triggering_actor }}
+          commit_user_email: ${{ format('{0}@users.noreply.github.com', github.triggering_actor) }}
+          create_branch: true

  commit_fbsource_artifacts:
-    needs: [download_artifacts, process_artifacts]
-    permissions:
-      # Used to push a commit to builds/facebook-fbsource
-      contents: write
-    if: inputs.force == true || (github.ref == 'refs/heads/main' && needs.process_artifacts.outputs.fbsource_branch_count == '0')
+    needs: download_artifacts
+    if: inputs.force == true || (github.ref == 'refs/heads/main' && needs.download_artifacts.outputs.fbsource_branch_count == '0')
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
@@ -314,10 +270,10 @@ jobs:
          name: compiled-rn
          path: compiled-rn/
      - name: Revert version changes
-        if: needs.process_artifacts.outputs.last_version_rn != ''
+        if: needs.download_artifacts.outputs.last_version_rn != ''
        env:
-          CURRENT_VERSION: ${{ needs.process_artifacts.outputs.current_version_rn }}
-          LAST_VERSION: ${{ needs.process_artifacts.outputs.last_version_rn }}
+          CURRENT_VERSION: ${{ needs.download_artifacts.outputs.current_version_rn }}
+          LAST_VERSION: ${{ needs.download_artifacts.outputs.last_version_rn }}
        run: |
          echo "Reverting $CURRENT_VERSION to $LAST_VERSION"
          grep -rl "$CURRENT_VERSION" ./compiled-rn || echo "No files found with $CURRENT_VERSION"
@@ -332,10 +288,10 @@ jobs:
          git --no-pager diff -U0 --cached | grep '^[+-]' | head -n 100
          echo "===================="
          # Ignore REVISION or lines removing @generated headers.
-          if git diff --cached ':(exclude)*REVISION' ':(exclude)*/eslint-plugin-react-hooks/package.json' | grep -vE "^(@@|diff|index|\-\-\-|\+\+\+|\- \* @generated SignedSource)" | grep "^[+-]" > /dev/null; then
+          if git diff --cached ':(exclude)*REVISION' | grep -vE "^(@@|diff|index|\-\-\-|\+\+\+|\- \* @generated SignedSource)" | grep "^[+-]" > /dev/null; then
            echo "Changes detected"
            echo "===== Changes ====="
-            git --no-pager diff --cached ':(exclude)*REVISION' ':(exclude)*/eslint-plugin-react-hooks/package.json' | grep -vE "^(@@|diff|index|\-\-\-|\+\+\+|\- \* @generated SignedSource)" | grep "^[+-]" | head -n 50
+            git --no-pager diff --cached ':(exclude)*REVISION' | grep -vE "^(@@|diff|index|\-\-\-|\+\+\+|\- \* @generated SignedSource)" | grep "^[+-]" | head -n 50
            echo "==================="
            echo "should_commit=true" >> "$GITHUB_OUTPUT"
          else
@@ -343,10 +299,10 @@ jobs:
            echo "should_commit=false" >> "$GITHUB_OUTPUT"
          fi
      - name: Re-apply version changes
-        if: inputs.force == true || (steps.check_should_commit.outputs.should_commit == 'true' && needs.process_artifacts.outputs.last_version_rn != '')
+        if: inputs.force == true || (steps.check_should_commit.outputs.should_commit == 'true' && needs.download_artifacts.outputs.last_version_rn != '')
        env:
-          CURRENT_VERSION: ${{ needs.process_artifacts.outputs.current_version_rn }}
-          LAST_VERSION: ${{ needs.process_artifacts.outputs.last_version_rn }}
+          CURRENT_VERSION: ${{ needs.download_artifacts.outputs.current_version_rn }}
+          LAST_VERSION: ${{ needs.download_artifacts.outputs.last_version_rn }}
        run: |
          echo "Re-applying $LAST_VERSION to $CURRENT_VERSION"
          grep -rl "$LAST_VERSION" ./compiled-rn || echo "No files found with $LAST_VERSION"
@@ -453,19 +409,15 @@ jobs:
        run: |
          git add .
          git status
-      - name: Check commit message
-        if: inputs.dry_run
-        run: |
-          git fetch origin --quiet
-          git show ${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha }} --no-patch --pretty=format:"%B"
      - name: Commit changes to branch
        if: inputs.force == true || steps.check_should_commit.outputs.should_commit == 'true'
-        run: |
-          git config --global user.email "${{ format('{0}@users.noreply.github.com', github.triggering_actor) }}"
-          git config --global user.name "${{ github.triggering_actor }}"
+        uses: stefanzweifel/git-auto-commit-action@v5
+        with:
+          commit_message: |
+            ${{ github.event.workflow_run.head_commit.message || format('Manual build of {0}', github.event.workflow_run.head_sha || github.sha) }}

-          git fetch origin --quiet
-          git commit -m "$(git show ${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha }} --no-patch --pretty=format:'%B%n%nDiffTrain build for [${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha }}](https://github.com/facebook/react/commit/${{ inputs.commit_sha || github.event.workflow_run.head_sha || github.sha}})')" || echo "No changes to commit"
-      - name: Push changes to branch
-        if: inputs.dry_run == false && (inputs.force == true || steps.check_should_commit.outputs.should_commit == 'true')
-        run: git push
+            DiffTrain build for [${{ github.event.workflow_run.head_sha || github.sha }}](https://github.com/facebook/react/commit/${{ github.event.workflow_run.head_sha || github.sha }})
+          branch: builds/facebook-fbsource
+          commit_user_name: ${{ github.triggering_actor }}
+          commit_user_email: ${{ format('{0}@users.noreply.github.com', github.triggering_actor) }}
+          create_branch: true
--- a/.github/workflows/runtime_discord_notify.yml
+++ b/.github/workflows/runtime_discord_notify.yml
@@ -4,33 +4,12 @@ on:
  pull_request_target:
    types: [opened, ready_for_review]
    paths-ignore:
-      - packages/react-devtools**
      - compiler/**
      - .github/workflows/compiler_**.yml
-      - .github/workflows/devtools**.yml
-
-permissions: {}

 jobs:
-  check_access:
-    if: ${{ github.event.pull_request.draft == false }}
-    runs-on: ubuntu-latest
-    outputs:
-      is_member_or_collaborator: ${{ steps.check_is_member_or_collaborator.outputs.is_member_or_collaborator }}
-    steps:
-      - run: echo ${{ github.event.pull_request.author_association }}
-      - name: Check is member or collaborator
-        id: check_is_member_or_collaborator
-        if: ${{ github.event.pull_request.author_association == 'MEMBER' || github.event.pull_request.author_association == 'COLLABORATOR' }}
-        run: echo "is_member_or_collaborator=true" >> "$GITHUB_OUTPUT"
-
  check_maintainer:
-    if: ${{ needs.check_access.outputs.is_member_or_collaborator == 'true' || needs.check_access.outputs.is_member_or_collaborator == true }}
-    needs: [check_access]
    uses: facebook/react/.github/workflows/shared_check_maintainer.yml@main
-    permissions:
-      # Used by check_maintainer
-      contents: read
    with:
      actor: ${{ github.event.pull_request.user.login }}

@@ -40,7 +19,7 @@ jobs:
    runs-on: ubuntu-latest
    steps:
      - name: Discord Webhook Action
-        uses: tsickert/discord-webhook@86dc739f3f165f16dadc5666051c367efa1692f4
+        uses: tsickert/discord-webhook@v6.0.0
        with:
          webhook-url: ${{ secrets.DISCORD_WEBHOOK_URL }}
          embed-author-name: ${{ github.event.pull_request.user.login }}
--- a/.github/workflows/runtime_eslint_plugin_e2e.yml
+++ b/.github/workflows/runtime_eslint_plugin_e2e.yml
@@ -7,8 +7,6 @@ on:
    paths-ignore:
      - compiler/**

-permissions: {}
-
 concurrency:
  group: ${{ github.workflow }}-${{ github.ref_name }}-${{ github.event.pull_request.number || github.run_id }}
  cancel-in-progress: true
@@ -37,29 +35,22 @@ jobs:
        with:
          node-version-file: '.nvmrc'
          cache: yarn
-          cache-dependency-path: |
-            yarn.lock
-            compiler/yarn.lock
+          cache-dependency-path: yarn.lock
      - name: Restore cached node_modules
        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: runtime-and-compiler-eslint_e2e-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'compiler/yarn.lock', 'fixtures/eslint-v*/yarn.lock') }}
+          path: "node_modules"
+          key: runtime-eslint_e2e-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock') }}
      - name: Ensure clean build directory
        run: rm -rf build
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn --cwd compiler install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - name: Install fixture dependencies
-        working-directory: ./fixtures/eslint-v${{ matrix.eslint_major }}
-        run: yarn --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
      - name: Build plugin
        working-directory: fixtures/eslint-v${{ matrix.eslint_major }}
        run: node build.mjs
+      - name: Install fixture dependencies
+        working-directory: ./fixtures/eslint-v${{ matrix.eslint_major }}
+        run: yarn --frozen-lockfile
      - name: Run lint test
        working-directory: ./fixtures/eslint-v${{ matrix.eslint_major }}
        run: yarn lint
--- a/.github/workflows/runtime_fuzz_tests.yml
+++ b/.github/workflows/runtime_fuzz_tests.yml
@@ -8,8 +8,6 @@ on:
      - main
  workflow_dispatch:

-permissions: {}
-
 env:
  TZ: /usr/share/zoneinfo/America/Los_Angeles

--- a/.github/workflows/runtime_prereleases.yml
+++ b/.github/workflows/runtime_prereleases.yml
@@ -13,45 +13,21 @@ on:
      dist_tag:
        required: true
        type: string
-      enableFailureNotification:
-        description: 'Whether to notify the team on Discord when the release fails. Useful if this workflow is called from an automation.'
-        required: false
-        type: boolean
-      only_packages:
-        description: Packages to publish (space separated)
-        type: string
-      skip_packages:
-        description: Packages to NOT publish (space separated)
-        type: string
-      dry:
-        required: true
-        description: Dry run instead of publish?
-        type: boolean
-        default: true
    secrets:
-      DISCORD_WEBHOOK_URL:
-        description: 'Discord webhook URL to notify on failure. Only required if enableFailureNotification is true.'
-        required: false
-      GH_TOKEN:
-        required: true
      NPM_TOKEN:
        required: true

-permissions: {}
-
 env:
  TZ: /usr/share/zoneinfo/America/Los_Angeles
  # https://github.com/actions/cache/blob/main/tips-and-workarounds.md#cache-segment-restore-timeout
  SEGMENT_DOWNLOAD_TIMEOUT_MINS: 1
+  GH_TOKEN: ${{ github.token }}
  NPM_TOKEN: ${{ secrets.NPM_TOKEN }}

 jobs:
  publish_prerelease:
    name: Publish prelease (${{ inputs.release_channel }}) ${{ inputs.commit_sha }} @${{ inputs.dist_tag }}
    runs-on: ubuntu-latest
-    permissions:
-      # We use github.token to download the build artifact from a previous runtime_build_and_test.yml run
-      actions: read
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-node@v4
@@ -63,50 +39,14 @@ jobs:
        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: runtime-release-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'scripts/release/yarn.lock') }}
+          path: "**/node_modules"
+          key: runtime-release-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'scripts/release/yarn.lock') }}
      - name: Ensure clean build directory
        run: rm -rf build
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn --cwd scripts/release install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: cp ./scripts/release/ci-npmrc ~/.npmrc
+      - run: yarn install --frozen-lockfile
+        working-directory: scripts/release
      - run: |
-          GH_TOKEN=${{ secrets.GH_TOKEN }} scripts/release/prepare-release-from-ci.js --skipTests -r ${{ inputs.release_channel }} --commit=${{ inputs.commit_sha }}
-      - name: Check prepared files
-        run: ls -R build/node_modules
-      - if: '${{ inputs.only_packages }}'
-        name: 'Publish ${{ inputs.only_packages }}'
-        run: |
-          scripts/release/publish.js \
-            --ci \
-            --skipTests \
-            --tags=${{ inputs.dist_tag }} \
-            --onlyPackages=${{ inputs.only_packages }} ${{ (inputs.dry && '') || '\'}}
-            ${{ inputs.dry && '--dry' || '' }}
-      - if: '${{ inputs.skip_packages }}'
-        name: 'Publish all packages EXCEPT ${{ inputs.skip_packages }}'
-        run: |
-          scripts/release/publish.js \
-            --ci \
-            --skipTests \
-            --tags=${{ inputs.dist_tag }} \
-            --skipPackages=${{ inputs.skip_packages }} ${{ (inputs.dry && '') || '\'}}
-            ${{ inputs.dry && '--dry' || '' }}
-      - if: '${{ !(inputs.skip_packages && inputs.only_packages) }}'
-        name: 'Publish all packages'
-        run: |
-          scripts/release/publish.js \
-            --ci \
-            --tags=${{ inputs.dist_tag }} ${{ (inputs.dry && '') || '\'}}
-            ${{ inputs.dry && '--dry' || '' }}
-      - name: Notify Discord on failure
-        if: failure() && inputs.enableFailureNotification == true
-        uses: tsickert/discord-webhook@86dc739f3f165f16dadc5666051c367efa1692f4
-        with:
-          webhook-url: ${{ secrets.DISCORD_WEBHOOK_URL }}
-          embed-author-name: "GitHub Actions"
-          embed-title: '[Runtime] Publish of ${{ inputs.release_channel }}@${{ inputs.dist_tag}} release failed'
-          embed-url: ${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}/attempts/${{ github.run_attempt }}
+          scripts/release/prepare-release-from-ci.js --skipTests -r ${{ inputs.release_channel }} --commit=${{ inputs.commit_sha }}
+          cp ./scripts/release/ci-npmrc ~/.npmrc
+          scripts/release/publish.js --ci --tags ${{ inputs.dist_tag }}
--- a/.github/workflows/runtime_prereleases_manual.yml
+++ b/.github/workflows/runtime_prereleases_manual.yml
@@ -5,57 +5,15 @@ on:
    inputs:
      prerelease_commit_sha:
        required: true
-      only_packages:
-        description: Packages to publish (space separated)
-        type: string
-      skip_packages:
-        description: Packages to NOT publish (space separated)
-        type: string
-      dry:
-        required: true
-        description: Dry run instead of publish?
-        type: boolean
-        default: true
-      experimental_only:
-        type: boolean
-        description: Only publish to the experimental tag
-        default: false
-      force_notify:
-        description: Force a Discord notification?
-        type: boolean
-        default: false
-
-permissions: {}

 env:
  TZ: /usr/share/zoneinfo/America/Los_Angeles

 jobs:
-  notify:
-    if: ${{ inputs.force_notify || inputs.dry == false || inputs.dry == 'false' }}
-    runs-on: ubuntu-latest
-    steps:
-      - name: Discord Webhook Action
-        uses: tsickert/discord-webhook@86dc739f3f165f16dadc5666051c367efa1692f4
-        with:
-          webhook-url: ${{ secrets.DISCORD_WEBHOOK_URL }}
-          embed-author-name: ${{ github.event.sender.login }}
-          embed-author-url: ${{ github.event.sender.html_url }}
-          embed-author-icon-url: ${{ github.event.sender.avatar_url }}
-          embed-title: "⚠️ Publishing ${{ inputs.experimental_only && 'EXPERIMENTAL' || 'CANARY & EXPERIMENTAL' }} release ${{ (inputs.dry && ' (dry run)') || '' }}"
-          embed-description: |
-            ```json
-            ${{ toJson(inputs) }}
-            ```
-          embed-url: https://github.com/facebook/react/actions/runs/${{ github.run_id }}

  publish_prerelease_canary:
-    if: ${{ !inputs.experimental_only }}
    name: Publish to Canary channel
    uses: facebook/react/.github/workflows/runtime_prereleases.yml@main
-    permissions:
-      # We use github.token to download the build artifact from a previous runtime_build_and_test.yml run
-      actions: read
    with:
      commit_sha: ${{ inputs.prerelease_commit_sha }}
      release_channel: stable
@@ -70,33 +28,20 @@ jobs:
      # downstream consumers might still expect that tag. We can remove this
      # after some time has elapsed and the change has been communicated.
      dist_tag: canary,next
-      only_packages: ${{ inputs.only_packages }}
-      skip_packages: ${{ inputs.skip_packages }}
-      dry: ${{ inputs.dry }}
    secrets:
      NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
-      GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}

  publish_prerelease_experimental:
    name: Publish to Experimental channel
    uses: facebook/react/.github/workflows/runtime_prereleases.yml@main
-    permissions:
-      # We use github.token to download the build artifact from a previous runtime_build_and_test.yml run
-      actions: read
    # NOTE: Intentionally running these jobs sequentially because npm
    # will sometimes fail if you try to concurrently publish two
    # different versions of the same package, even if they use different
    # dist tags.
    needs: publish_prerelease_canary
-    # Ensures the job runs even if canary is skipped
-    if: always()
    with:
      commit_sha: ${{ inputs.prerelease_commit_sha }}
      release_channel: experimental
      dist_tag: experimental
-      only_packages: ${{ inputs.only_packages }}
-      skip_packages: ${{ inputs.skip_packages }}
-      dry: ${{ inputs.dry }}
    secrets:
      NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
-      GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
--- a/.github/workflows/runtime_prereleases_nightly.yml
+++ b/.github/workflows/runtime_prereleases_nightly.yml
@@ -5,8 +5,6 @@ on:
    # At 10 minutes past 16:00 on Mon, Tue, Wed, Thu, and Fri
    - cron: 10 16 * * 1,2,3,4,5

-permissions: {}
-
 env:
  TZ: /usr/share/zoneinfo/America/Los_Angeles

@@ -14,26 +12,16 @@ jobs:
  publish_prerelease_canary:
    name: Publish to Canary channel
    uses: facebook/react/.github/workflows/runtime_prereleases.yml@main
-    permissions:
-      # We use github.token to download the build artifact from a previous runtime_build_and_test.yml run
-      actions: read
    with:
      commit_sha: ${{ github.sha }}
      release_channel: stable
      dist_tag: canary,next
-      enableFailureNotification: true
-      dry: false
    secrets:
-      DISCORD_WEBHOOK_URL: ${{ secrets.DISCORD_WEBHOOK_URL }}
      NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
-      GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}

  publish_prerelease_experimental:
    name: Publish to Experimental channel
    uses: facebook/react/.github/workflows/runtime_prereleases.yml@main
-    permissions:
-      # We use github.token to download the build artifact from a previous runtime_build_and_test.yml run
-      actions: read
    # NOTE: Intentionally running these jobs sequentially because npm
    # will sometimes fail if you try to concurrently publish two
    # different versions of the same package, even if they use different
@@ -43,9 +31,5 @@ jobs:
      commit_sha: ${{ github.sha }}
      release_channel: experimental
      dist_tag: experimental
-      enableFailureNotification: true
-      dry: false
    secrets:
-      DISCORD_WEBHOOK_URL: ${{ secrets.DISCORD_WEBHOOK_URL }}
      NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
-      GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
--- a/.github/workflows/runtime_releases_from_npm_manual.yml
+++ b/.github/workflows/runtime_releases_from_npm_manual.yml
@@ -31,12 +31,11 @@ on:
        type: boolean
        default: false

-permissions: {}
-
 env:
  TZ: /usr/share/zoneinfo/America/Los_Angeles
  # https://github.com/actions/cache/blob/main/tips-and-workarounds.md#cache-segment-restore-timeout
  SEGMENT_DOWNLOAD_TIMEOUT_MINS: 1
+  GH_TOKEN: ${{ github.token }}
  NPM_TOKEN: ${{ secrets.NPM_TOKEN }}

 jobs:
@@ -45,7 +44,7 @@ jobs:
    runs-on: ubuntu-latest
    steps:
      - name: Discord Webhook Action
-        uses: tsickert/discord-webhook@86dc739f3f165f16dadc5666051c367efa1692f4
+        uses: tsickert/discord-webhook@v6.0.0
        with:
          webhook-url: ${{ secrets.DISCORD_WEBHOOK_URL }}
          embed-author-name: ${{ github.event.sender.login }}
@@ -72,15 +71,13 @@ jobs:
        uses: actions/cache@v4
        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: runtime-release-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'scripts/release/yarn.lock') }}
+          path: "**/node_modules"
+          key: runtime-release-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('yarn.lock', 'scripts/release/yarn.lock') }}
      - name: Ensure clean build directory
        run: rm -rf build
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
-      - run: yarn --cwd scripts/release install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
+      - run: yarn install --frozen-lockfile
+        working-directory: scripts/release
      - run: cp ./scripts/release/ci-npmrc ~/.npmrc
      - if: '${{ inputs.only_packages }}'
        name: 'Prepare ${{ inputs.only_packages }} from NPM'
@@ -110,7 +107,7 @@ jobs:
            --tags=${{ inputs.tags }} \
            --publishVersion=${{ inputs.version_to_publish }} \
            --onlyPackages=${{ inputs.only_packages }} ${{ (inputs.dry && '') || '\'}}
-            ${{ inputs.dry && '--dry' || '' }}
+            ${{ inputs.dry && '--dry'}}
      - if: '${{ inputs.skip_packages }}'
        name: 'Publish all packages EXCEPT ${{ inputs.skip_packages }}'
        run: |
@@ -119,7 +116,7 @@ jobs:
            --tags=${{ inputs.tags }} \
            --publishVersion=${{ inputs.version_to_publish }} \
            --skipPackages=${{ inputs.skip_packages }} ${{ (inputs.dry && '') || '\'}}
-            ${{ inputs.dry && '--dry' || '' }}
+            ${{ inputs.dry && '--dry'}}
      - name: Archive released package for debugging
        uses: actions/upload-artifact@v4
        with:
--- a/.github/workflows/shared_check_maintainer.yml
+++ b/.github/workflows/shared_check_maintainer.yml
@@ -6,12 +6,14 @@ on:
      actor:
        required: true
        type: string
+      is_remote:
+        required: false
+        type: boolean
+        default: false
    outputs:
      is_core_team:
        value: ${{ jobs.check_maintainer.outputs.is_core_team }}

-permissions: {}
-
 env:
  TZ: /usr/share/zoneinfo/America/Los_Angeles
  # https://github.com/actions/cache/blob/main/tips-and-workarounds.md#cache-segment-restore-timeout
@@ -20,12 +22,10 @@ env:
 jobs:
  check_maintainer:
    runs-on: ubuntu-latest
-    permissions:
-      # We fetch the contents of the MAINTAINERS file
-      contents: read
    outputs:
      is_core_team: ${{ steps.check_if_actor_is_maintainer.outputs.result }}
    steps:
+      - uses: actions/checkout@v4
      - name: Check if actor is maintainer
        id: check_if_actor_is_maintainer
        uses: actions/github-script@v7
@@ -33,20 +33,33 @@ jobs:
          script: |
            const fs = require('fs');
            const actor = '${{ inputs.actor }}';
-            const res = await github.rest.repos.getContent({
-              owner: 'facebook',
-              repo: 'react',
-              path: 'MAINTAINERS',
-              ref: 'main',
-              headers: { Accept: 'application/vnd.github+json' }
-            });
-            if (res.status !== 200) {
-              console.error(res);
-              throw new Error('Unable to fetch MAINTAINERS file');
+            let isRemote = ${{ inputs.is_remote }};
+            if (typeof isRemote === 'string') {
+              isRemote = isRemote === 'true';
            }
-            content = Buffer.from(res.data.content, 'base64').toString();
-            if (content == null || typeof content !== 'string') {
-              throw new Error('Unable to retrieve MAINTAINERS file');
+            if (typeof isRemote !== 'boolean') {
+              throw new Error(`Invalid \`isRemote\` input. Expected a boolean, got: ${isRemote}`);
+            }
+
+            let content = null;
+            if (isRemote === true) {
+              const res = await github.rest.repos.getContent({
+                owner: 'facebook',
+                repo: 'react',
+                path: 'MAINTAINERS',
+                ref: 'main',
+                headers: { Accept: 'application/vnd.github+json' }
+              });
+              if (res.status !== 200) {
+                console.error(res);
+                throw new Error('Unable to fetch MAINTAINERS file');
+              }
+              content = Buffer.from(res.data.content, 'base64').toString();
+            } else {
+              content = await fs.readFileSync('./MAINTAINERS', { encoding: 'utf8' });
+            }
+            if (content === null) {
+              throw new Error('Unable to retrieve local or http MAINTAINERS file');
            }

            const maintainers = new Set(content.split('\n'));
--- a/.github/workflows/shared_cleanup_merged_branch_caches.yml
+++ b/.github/workflows/shared_cleanup_merged_branch_caches.yml
@@ -1,41 +0,0 @@
-# https://github.com/actions/cache/blob/main/tips-and-workarounds.md#force-deletion-of-caches-overriding-default-cache-eviction-policy
-
-name: (Shared) Cleanup Merged Branch Caches
-on:
-  pull_request:
-    types:
-      - closed
-  workflow_dispatch:
-    inputs:
-      pr_number:
-        required: true
-        type: string
-
-permissions: {}
-
-jobs:
-  cleanup:
-    runs-on: ubuntu-latest
-    permissions:
-      # `actions:write` permission is required to delete caches
-      #   See also: https://docs.github.com/en/rest/actions/cache?apiVersion=2022-11-28#delete-a-github-actions-cache-for-a-repository-using-a-cache-id
-      actions: write
-      contents: read
-    steps:
-      - name: Cleanup
-        run: |
-          echo "Fetching list of cache key"
-          cacheKeysForPR=$(gh cache list --ref $BRANCH --limit 100 --json id --jq '.[].id')
-
-          ## Setting this to not fail the workflow while deleting cache keys.
-          set +e
-          for cacheKey in $cacheKeysForPR
-          do
-              gh cache delete $cacheKey
-              echo "Deleting $cacheKey"
-          done
-          echo "Done"
-        env:
-          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-          GH_REPO: ${{ github.repository }}
-          BRANCH: refs/pull/${{ inputs.pr_number || github.event.pull_request.number }}/merge
--- a/.github/workflows/shared_cleanup_stale_branch_caches.yml
+++ b/.github/workflows/shared_cleanup_stale_branch_caches.yml
@@ -1,36 +0,0 @@
-# https://github.com/actions/cache/blob/main/tips-and-workarounds.md#force-deletion-of-caches-overriding-default-cache-eviction-policy
-
-name: (Shared) Cleanup Stale Branch Caches
-on:
-  schedule:
-    # Every 6 hours
-    - cron: 0 */6 * * *
-  workflow_dispatch:
-
-permissions: {}
-
-jobs:
-  cleanup:
-    runs-on: ubuntu-latest
-    permissions:
-      # `actions:write` permission is required to delete caches
-      #   See also: https://docs.github.com/en/rest/actions/cache?apiVersion=2022-11-28#delete-a-github-actions-cache-for-a-repository-using-a-cache-id
-      actions: write
-      contents: read
-    steps:
-      - name: Cleanup
-        run: |
-          echo "Fetching list of cache keys"
-          cacheKeysForPR=$(gh cache list --limit 100 --json id,ref --jq '.[] | select(.ref != "refs/heads/main") | .id')
-
-          ## Setting this to not fail the workflow while deleting cache keys.
-          set +e
-          for cacheKey in $cacheKeysForPR
-          do
-              gh cache delete $cacheKey
-              echo "Deleting $cacheKey"
-          done
-          echo "Done"
-        env:
-          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-          GH_REPO: ${{ github.repository }}
--- a/.github/workflows/shared_close_direct_sync_branch_prs.yml
+++ b/.github/workflows/shared_close_direct_sync_branch_prs.yml
@@ -5,8 +5,6 @@ on:
    branches:
      - 'builds/facebook-**'

-permissions: {}
-
 env:
  TZ: /usr/share/zoneinfo/America/Los_Angeles
  # https://github.com/actions/cache/blob/main/tips-and-workarounds.md#cache-segment-restore-timeout
@@ -15,10 +13,6 @@ env:
 jobs:
  close_pr:
    runs-on: ubuntu-latest
-    permissions:
-      # Used to create a review and close PRs
-      pull-requests: write
-      contents: write
    steps:
      - name: Close PR
        uses: actions/github-script@v7
--- a/.github/workflows/shared_label_core_team_prs.yml
+++ b/.github/workflows/shared_label_core_team_prs.yml
@@ -2,9 +2,6 @@ name: (Shared) Label Core Team PRs

 on:
  pull_request_target:
-    types: [opened]
-
-permissions: {}

 env:
  TZ: /usr/share/zoneinfo/America/Los_Angeles
@@ -12,24 +9,8 @@ env:
  SEGMENT_DOWNLOAD_TIMEOUT_MINS: 1

 jobs:
-  check_access:
-    runs-on: ubuntu-latest
-    outputs:
-      is_member_or_collaborator: ${{ steps.check_is_member_or_collaborator.outputs.is_member_or_collaborator }}
-    steps:
-      - run: echo ${{ github.event.pull_request.author_association }}
-      - name: Check is member or collaborator
-        id: check_is_member_or_collaborator
-        if: ${{ github.event.pull_request.author_association == 'MEMBER' || github.event.pull_request.author_association == 'COLLABORATOR' }}
-        run: echo "is_member_or_collaborator=true" >> "$GITHUB_OUTPUT"
-
  check_maintainer:
-    if: ${{ needs.check_access.outputs.is_member_or_collaborator == 'true' || needs.check_access.outputs.is_member_or_collaborator == true }}
-    needs: [check_access]
    uses: facebook/react/.github/workflows/shared_check_maintainer.yml@main
-    permissions:
-      # Used by check_maintainer
-      contents: read
    with:
      actor: ${{ github.event.pull_request.user.login }}

@@ -37,11 +18,6 @@ jobs:
    if: ${{ needs.check_maintainer.outputs.is_core_team == 'true' }}
    runs-on: ubuntu-latest
    needs: check_maintainer
-    permissions:
-      # Used to add labels on issues
-      issues: write
-      # Used to add labels on PRs
-      pull-requests: write
    steps:
      - name: Label PR as React Core Team
        uses: actions/github-script@v7
--- a/.github/workflows/shared_lint.yml
+++ b/.github/workflows/shared_lint.yml
@@ -5,8 +5,6 @@ on:
    branches: [main]
  pull_request:

-permissions: {}
-
 concurrency:
  group: ${{ github.workflow }}-${{ github.ref_name }}-${{ github.event.pull_request.number || github.run_id }}
  cancel-in-progress: true
@@ -29,15 +27,12 @@ jobs:
          cache-dependency-path: yarn.lock
      - name: Restore cached node_modules
        uses: actions/cache@v4
-        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: shared-lint-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('**/yarn.lock') }}
+          path: "**/node_modules"
+          key: shared-lint-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('**/yarn.lock') }}
      - name: Ensure clean build directory
        run: rm -rf build
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
      - run: yarn prettier-check

  eslint:
@@ -52,15 +47,12 @@ jobs:
          cache-dependency-path: yarn.lock
      - name: Restore cached node_modules
        uses: actions/cache@v4
-        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: shared-lint-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('**/yarn.lock') }}
+          path: "**/node_modules"
+          key: shared-lint-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('**/yarn.lock') }}
      - name: Ensure clean build directory
        run: rm -rf build
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
      - run: node ./scripts/tasks/eslint

  check_license:
@@ -75,15 +67,12 @@ jobs:
          cache-dependency-path: yarn.lock
      - name: Restore cached node_modules
        uses: actions/cache@v4
-        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: shared-lint-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('**/yarn.lock') }}
+          path: "**/node_modules"
+          key: shared-lint-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('**/yarn.lock') }}
      - name: Ensure clean build directory
        run: rm -rf build
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
      - run: ./scripts/ci/check_license.sh

  test_print_warnings:
@@ -98,13 +87,10 @@ jobs:
          cache-dependency-path: yarn.lock
      - name: Restore cached node_modules
        uses: actions/cache@v4
-        id: node_modules
        with:
-          path: |
-            **/node_modules
-          key: shared-lint-node_modules-v6-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('**/yarn.lock') }}
+          path: "**/node_modules"
+          key: shared-lint-node_modules-${{ runner.arch }}-${{ runner.os }}-${{ hashFiles('**/yarn.lock') }}
      - name: Ensure clean build directory
        run: rm -rf build
      - run: yarn install --frozen-lockfile
-        if: steps.node_modules.outputs.cache-hit != 'true'
      - run: ./scripts/ci/test_print_warnings.sh
--- a/.github/workflows/shared_stale.yml
+++ b/.github/workflows/shared_stale.yml
@@ -6,11 +6,6 @@ on:
    - cron: '0 * * * *'
  workflow_dispatch:

-permissions:
-  # https://github.com/actions/stale/tree/v9/?tab=readme-ov-file#recommended-permissions
-  issues: write
-  pull-requests: write
-
 env:
  TZ: /usr/share/zoneinfo/America/Los_Angeles

--- a/.gitignore
+++ b/.gitignore
@@ -23,7 +23,6 @@ chrome-user-data
 .vscode
 *.swp
 *.swo
-/tmp

 packages/react-devtools-core/dist
 packages/react-devtools-extensions/chrome/build
--- a/.nvmrc
+++ b/.nvmrc
@@ -1 +1 @@
-v20.19.0
+v18.20.1
--- a/.prettierrc.js
+++ b/.prettierrc.js
@@ -3,12 +3,13 @@
 const {esNextPaths} = require('./scripts/shared/pathsByLanguageVersion');

 module.exports = {
+  plugins: ['prettier-plugin-hermes-parser'],
  bracketSpacing: false,
  singleQuote: true,
  bracketSameLine: true,
  trailingComma: 'es5',
  printWidth: 80,
-  parser: 'flow',
+  parser: 'hermes',
  arrowParens: 'avoid',
  overrides: [
    {
--- a/CHANGELOG-canary.md
+++ b/CHANGELOG-canary.md
@@ -0,0 +1,18 @@
+## March 22, 2024 (18.3.0-canary-670811593-20240322)
+
+## React
+- Added `useActionState` to replace `useFormState` and added `pending` value ([#28491](https://github.com/facebook/react/pull/28491)).
+
+## October 5, 2023 (18.3.0-canary-546178f91-20231005)
+
+### React
+
+- Added support for async functions to be passed to `startTransition`. 
+- `useTransition` now triggers the nearest error boundary instead of a global error.
+- Added `useOptimistic`, a new Hook for handling optimistic UI updates. It optimistically updates the UI before receiving confirmation from a server or external source.
+
+### React DOM
+
+- Added support for passing async functions to the `action` prop on `<form>`. When the function passed to `action` is marked with [`'use server'`](https://react.dev/reference/react/use-server), the form is [progressively enhanced](https://developer.mozilla.org/en-US/docs/Glossary/Progressive_Enhancement).
+- Added `useFormStatus`, a new Hook for checking the submission state of a form.
+- Added `useFormState`, a new Hook for updating state upon form submission. When the function passed to `useFormState` is marked with [`'use server'`](https://react.dev/reference/react/use-server), the update is [progressively enhanced](https://developer.mozilla.org/en-US/docs/Glossary/Progressive_Enhancement).
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,55 +1,3 @@
-## 19.1.1 (July 28, 2025)
-
-### React
-* Fixed Owner Stacks to work with ES2015 function.name semantics ([#33680](https://github.com/facebook/react/pull/33680) by @hoxyq)
-
-## 19.1.0 (March 28, 2025)
-
-### Owner Stack
-
-An Owner Stack is a string representing the components that are directly responsible for rendering a particular component. You can log Owner Stacks when debugging or use Owner Stacks to enhance error overlays or other development tools. Owner Stacks are only available in development builds. Component Stacks in production are unchanged.
-
-* An Owner Stack is a development-only stack trace that helps identify which components are responsible for rendering a particular component. An Owner Stack is distinct from a Component Stacks, which shows the hierarchy of components leading to an error.
-* The [captureOwnerStack API](https://react.dev/reference/react/captureOwnerStack) is only available in development mode and returns a Owner Stack, if available. The API can be used to enhance error overlays or log component relationships when debugging. [#29923](https://github.com/facebook/react/pull/29923), [#32353](https://github.com/facebook/react/pull/32353), [#30306](https://github.com/facebook/react/pull/30306),
-[#32538](https://github.com/facebook/react/pull/32538), [#32529](https://github.com/facebook/react/pull/32529), [#32538](https://github.com/facebook/react/pull/32538)
-
-### React
-* Enhanced support for Suspense boundaries to be used anywhere, including the client, server, and during hydration. [#32069](https://github.com/facebook/react/pull/32069), [#32163](https://github.com/facebook/react/pull/32163), [#32224](https://github.com/facebook/react/pull/32224), [#32252](https://github.com/facebook/react/pull/32252)
-* Reduced unnecessary client rendering through improved hydration scheduling [#31751](https://github.com/facebook/react/pull/31751)
-* Increased priority of client rendered Suspense boundaries [#31776](https://github.com/facebook/react/pull/31776)
-* Fixed frozen fallback states by rendering unfinished Suspense boundaries on the client. [#31620](https://github.com/facebook/react/pull/31620)
-* Reduced garbage collection pressure by improving Suspense boundary retries. [#31667](https://github.com/facebook/react/pull/31667)
-* Fixed erroneous “Waiting for Paint” log when the passive effect phase was not delayed [#31526](https://github.com/facebook/react/pull/31526)
-* Fixed a regression causing key warnings for flattened positional children in development mode. [#32117](https://github.com/facebook/react/pull/32117)
-* Updated `useId` to use valid CSS selectors, changing format from `:r123:` to `«r123»`. [#32001](https://github.com/facebook/react/pull/32001)
-* Added a dev-only warning for null/undefined created in useEffect, useInsertionEffect, and useLayoutEffect. [#32355](https://github.com/facebook/react/pull/32355)
-* Fixed a bug where dev-only methods were exported in production builds. React.act is no longer available in production builds. [#32200](https://github.com/facebook/react/pull/32200)
-* Improved consistency across prod and dev to improve compatibility with Google Closure Compiler and bindings [#31808](https://github.com/facebook/react/pull/31808)
-* Improve passive effect scheduling for consistent task yielding. [#31785](https://github.com/facebook/react/pull/31785)
-* Fixed asserts in React Native when passChildrenWhenCloningPersistedNodes is enabled for OffscreenComponent rendering. [#32528](https://github.com/facebook/react/pull/32528)
-* Fixed component name resolution for Portal [#32640](https://github.com/facebook/react/pull/32640)
-* Added support for beforetoggle and toggle events on the dialog element. [#32479](https://github.com/facebook/react/pull/32479)
-
-### React DOM
-* Fixed double warning when the `href` attribute is an empty string [#31783](https://github.com/facebook/react/pull/31783)
- * Fixed an edge case where `getHoistableRoot()` didn’t work properly when the container was a Document [#32321](https://github.com/facebook/react/pull/32321)
-* Removed support for using HTML comments (e.g. `<!-- -->`) as a DOM container. [#32250](https://github.com/facebook/react/pull/32250)
-* Added support for `<script>` and `<template>` tags to be nested within `<select>` tags. [#31837](https://github.com/facebook/react/pull/31837)
-* Fixed responsive images to be preloaded as HTML instead of headers [#32445](https://github.com/facebook/react/pull/32445)
-
-### use-sync-external-store
-* Added `exports` field to `package.json` for `use-sync-external-store` to support various entrypoints. [#25231](https://github.com/facebook/react/pull/25231)
-
-### React Server Components
-* Added `unstable_prerender`, a new experimental API for prerendering React Server Components on the server [#31724](https://github.com/facebook/react/pull/31724)
-* Fixed an issue where streams would hang when receiving new chunks after a global error [#31840](https://github.com/facebook/react/pull/31840), [#31851](https://github.com/facebook/react/pull/31851)
-* Fixed an issue where pending chunks were counted twice. [#31833](https://github.com/facebook/react/pull/31833)
-* Added support for streaming in edge environments [#31852](https://github.com/facebook/react/pull/31852)
-* Added support for sending custom error names from a server so that they are available in the client for console replaying. [#32116](https://github.com/facebook/react/pull/32116)
-* Updated the server component wire format to remove IDs for hints and console.log because they have no return value [#31671](https://github.com/facebook/react/pull/31671)
-* Exposed `registerServerReference` in client builds to handle server references in different environments. [#32534](https://github.com/facebook/react/pull/32534)
-* Added react-server-dom-parcel package which integrates Server Components with the [Parcel bundler](https://parceljs.org/) [#31725](https://github.com/facebook/react/pull/31725), [#32132](https://github.com/facebook/react/pull/32132), [#31799](https://github.com/facebook/react/pull/31799), [#32294](https://github.com/facebook/react/pull/32294), [#31741](https://github.com/facebook/react/pull/31741)
-
 ## 19.0.0 (December 5, 2024)

 Below is a list of all new features, APIs, deprecations, and breaking changes. Read [React 19 release post](https://react.dev/blog/2024/04/25/react-19) and [React 19 upgrade guide](https://react.dev/blog/2024/04/25/react-19-upgrade-guide) for more information.
--- a/1
+++ b/1
@@ -1,6 +1,5 @@
 acdlite
 eps1lon
-EugeneChoi4
 gaearon
 gnoff
 unstubbable
--- a/ReactVersions.js
+++ b/ReactVersions.js
@@ -18,7 +18,7 @@
 //
 //   0.0.0-experimental-241c4467e-20200129

-const ReactVersion = '19.2.0';
+const ReactVersion = '19.1.0';

 // The label used by the @canary channel. Represents the upcoming release's
 // stability. Most of the time, this will be "canary", but we may temporarily
@@ -33,7 +33,7 @@ const canaryChannelLabel = 'canary';
 const rcNumber = 0;

 const stablePackages = {
-  'eslint-plugin-react-hooks': '6.1.0',
+  'eslint-plugin-react-hooks': '5.2.0',
  'jest-react': '0.17.0',
  react: ReactVersion,
  'react-art': ReactVersion,
@@ -42,12 +42,12 @@ const stablePackages = {
  'react-server-dom-turbopack': ReactVersion,
  'react-server-dom-parcel': ReactVersion,
  'react-is': ReactVersion,
-  'react-reconciler': '0.33.0',
-  'react-refresh': '0.18.0',
+  'react-reconciler': '0.32.0',
+  'react-refresh': '0.17.0',
  'react-test-renderer': ReactVersion,
-  'use-subscription': '1.12.0',
-  'use-sync-external-store': '1.6.0',
-  scheduler: '0.27.0',
+  'use-subscription': '1.11.0',
+  'use-sync-external-store': '1.5.0',
+  scheduler: '0.26.0',
 };

 // These packages do not exist in the @canary or @latest channel, only
--- a/babel.config-ts.js
+++ b/babel.config-ts.js
@@ -8,7 +8,6 @@ module.exports = {
    '@babel/plugin-syntax-jsx',
    '@babel/plugin-transform-flow-strip-types',
    ['@babel/plugin-transform-class-properties', {loose: true}],
-    ['@babel/plugin-transform-private-methods', {loose: true}],
    '@babel/plugin-transform-classes',
  ],
  presets: [
--- a/babel.config.js
+++ b/babel.config.js
@@ -4,7 +4,8 @@ module.exports = {
  plugins: [
    '@babel/plugin-syntax-jsx',
    '@babel/plugin-transform-flow-strip-types',
-    ['@babel/plugin-proposal-class-properties', {loose: true}],
+    ['@babel/plugin-transform-class-properties', {loose: true}],
+    '@babel/plugin-transform-classes',
    'syntax-trailing-function-commas',
    [
      '@babel/plugin-proposal-object-rest-spread',
--- a/compiler/.gitignore
+++ b/compiler/.gitignore
@@ -1,14 +1,28 @@
 .DS_Store
 .spr.yml

+# Generated by Cargo
+# will have compiled files and executables
+debug/
+target/
+
+# These are backup files generated by rustfmt
+**/*.rs.bk
+
+# MSVC Windows builds of rustc generate these, which store debugging information
+*.pdb
+
 node_modules
 .watchmanconfig
 .watchman-cookie-*
 dist
 .vscode
 !packages/playground/.vscode
+.spr.yml
 testfilter.txt

+bundle-oss.sh
+
 # forgive
 *.vsix
 .vscode-test
--- a/compiler/CHANGELOG.md
+++ b/compiler/CHANGELOG.md
@@ -1,65 +0,0 @@
-## 19.1.0-rc.2 (May 14, 2025)
-
-## babel-plugin-react-compiler
-
-* Fix for string attribute values with emoji [#33096](https://github.com/facebook/react/pull/33096) by [@josephsavona](https://github.com/josephsavona)
-
-## 19.1.0-rc.1 (April 21, 2025)
-
-## eslint-plugin-react-hooks
-* Temporarily disable ref access in render validation [#32839](https://github.com/facebook/react/pull/32839) by [@poteto](https://github.com/poteto)
-* Fix type error with recommended config [#32666](https://github.com/facebook/react/pull/32666) by [@niklasholm](https://github.com/niklasholm)
-* Merge rule from eslint-plugin-react-compiler into `react-hooks` plugin [#32416](https://github.com/facebook/react/pull/32416) by [@michaelfaith](https://github.com/michaelfaith)
-* Add dev dependencies for typescript migration [#32279](https://github.com/facebook/react/pull/32279) by [@michaelfaith](https://github.com/michaelfaith)
-* Support v9 context api [#32045](https://github.com/facebook/react/pull/32045) by [@michaelfaith](https://github.com/michaelfaith)
-* Support eslint 8+ flat plugin syntax out of the box for eslint-plugin-react-compiler [#32120](https://github.com/facebook/react/pull/32120) by [@orta](https://github.com/orta)
-
-## babel-plugin-react-compiler
-* Support satisfies operator [#32742](https://github.com/facebook/react/pull/32742) by [@rodrigofariow](https://github.com/rodrigofariow)
-* Fix inferEffectDependencies lint false positives [#32769](https://github.com/facebook/react/pull/32769) by [@mofeiZ](https://github.com/mofeiZ)
-* Fix hoisting of let declarations [#32724](https://github.com/facebook/react/pull/32724) by [@mofeiZ](https://github.com/mofeiZ)
-* Avoid failing builds when import specifiers conflict or shadow vars [#32663](https://github.com/facebook/react/pull/32663) by [@mofeiZ](https://github.com/mofeiZ)
-* Optimize components declared with arrow function and implicit return and `compilationMode: 'infer'` [#31792](https://github.com/facebook/react/pull/31792) by [@dimaMachina](https://github.com/dimaMachina)
-* Validate static components [#32683](https://github.com/facebook/react/pull/32683) by [@josephsavona](https://github.com/josephsavona)
-* Hoist dependencies from functions more conservatively [#32616](https://github.com/facebook/react/pull/32616) by [@mofeiZ](https://github.com/mofeiZ)
-* Implement NumericLiteral as ObjectPropertyKey [#31791](https://github.com/facebook/react/pull/31791) by [@dimaMachina](https://github.com/dimaMachina)
-* Avoid bailouts when inserting gating [#32598](https://github.com/facebook/react/pull/32598) by [@mofeiZ](https://github.com/mofeiZ)
-* Stop bailing out early for hoisted gated functions [#32597](https://github.com/facebook/react/pull/32597) by [@mofeiZ](https://github.com/mofeiZ)
-* Add shape for Array.from [#32522](https://github.com/facebook/react/pull/32522) by [@mofeiZ](https://github.com/mofeiZ)
-* Patch array and argument spread mutability [#32521](https://github.com/facebook/react/pull/32521) by [@mofeiZ](https://github.com/mofeiZ)
-* Make CompilerError compatible with reflection [#32539](https://github.com/facebook/react/pull/32539) by [@poteto](https://github.com/poteto)
-* Add simple walltime measurement [#32331](https://github.com/facebook/react/pull/32331) by [@poteto](https://github.com/poteto)
-* Improve error messages for unhandled terminal and instruction kinds [#32324](https://github.com/facebook/react/pull/32324) by [@inottn](https://github.com/inottn)
-* Handle TSInstantiationExpression in lowerExpression [#32302](https://github.com/facebook/react/pull/32302) by [@inottn](https://github.com/inottn)
-* Fix invalid Array.map type [#32095](https://github.com/facebook/react/pull/32095) by [@mofeiZ](https://github.com/mofeiZ)
-* Patch for JSX escape sequences in @babel/generator [#32131](https://github.com/facebook/react/pull/32131) by [@mofeiZ](https://github.com/mofeiZ)
-* `JSXText` emits incorrect with bracket [#32138](https://github.com/facebook/react/pull/32138) by [@himself65](https://github.com/himself65)
-* Validation against calling impure functions [#31960](https://github.com/facebook/react/pull/31960) by [@josephsavona](https://github.com/josephsavona)
-* Always target node [#32091](https://github.com/facebook/react/pull/32091) by [@poteto](https://github.com/poteto)
-* Patch compilationMode:infer object method edge case [#32055](https://github.com/facebook/react/pull/32055) by [@mofeiZ](https://github.com/mofeiZ)
-* Generate ts defs [#31994](https://github.com/facebook/react/pull/31994) by [@poteto](https://github.com/poteto)
-* Relax react peer dep requirement [#31915](https://github.com/facebook/react/pull/31915) by [@poteto](https://github.com/poteto)
-* Allow type cast expressions with refs [#31871](https://github.com/facebook/react/pull/31871) by [@josephsavona](https://github.com/josephsavona)
-* Add shape for global Object.keys [#31583](https://github.com/facebook/react/pull/31583) by [@mofeiZ](https://github.com/mofeiZ)
-* Optimize method calls w props receiver [#31775](https://github.com/facebook/react/pull/31775) by [@josephsavona](https://github.com/josephsavona)
-* Fix dropped ref with spread props in InlineJsxTransform [#31726](https://github.com/facebook/react/pull/31726) by [@jackpope](https://github.com/jackpope)
-* Support for non-declatation for in/of iterators [#31710](https://github.com/facebook/react/pull/31710) by [@mvitousek](https://github.com/mvitousek)
-* Support for context variable loop iterators [#31709](https://github.com/facebook/react/pull/31709) by [@mvitousek](https://github.com/mvitousek)
-* Replace deprecated dependency in `eslint-plugin-react-compiler` [#31629](https://github.com/facebook/react/pull/31629) by [@rakleed](https://github.com/rakleed)
-* Support enableRefAsProp in jsx transform [#31558](https://github.com/facebook/react/pull/31558) by [@jackpope](https://github.com/jackpope)
-* Fix: ref.current now correctly reactive [#31521](https://github.com/facebook/react/pull/31521) by [@mofeiZ](https://github.com/mofeiZ)
-* Outline JSX with non-jsx children [#31442](https://github.com/facebook/react/pull/31442) by [@gsathya](https://github.com/gsathya)
-* Outline jsx with duplicate attributes [#31441](https://github.com/facebook/react/pull/31441) by [@gsathya](https://github.com/gsathya)
-* Store original and new prop names [#31440](https://github.com/facebook/react/pull/31440) by [@gsathya](https://github.com/gsathya)
-* Stabilize compiler output: sort deps and decls by name [#31362](https://github.com/facebook/react/pull/31362) by [@mofeiZ](https://github.com/mofeiZ)
-* Bugfix for hoistable deps for nested functions [#31345](https://github.com/facebook/react/pull/31345) by [@mofeiZ](https://github.com/mofeiZ)
-* Remove compiler runtime-compat fixture library [#31430](https://github.com/facebook/react/pull/31430) by [@poteto](https://github.com/poteto)
-* Wrap inline jsx transform codegen in conditional [#31267](https://github.com/facebook/react/pull/31267) by [@jackpope](https://github.com/jackpope)
-* Check if local identifier is a hook when resolving globals [#31384](https://github.com/facebook/react/pull/31384) by [@poteto](https://github.com/poteto)
-* Handle member expr as computed property [#31344](https://github.com/facebook/react/pull/31344) by [@gsathya](https://github.com/gsathya)
-* Fix to ref access check to ban ref?.current [#31360](https://github.com/facebook/react/pull/31360) by [@mvitousek](https://github.com/mvitousek)
-* InlineJSXTransform transforms jsx inside function expressions [#31282](https://github.com/facebook/react/pull/31282) by [@josephsavona](https://github.com/josephsavona)
-
-## Other
-* Add shebang to banner [#32225](https://github.com/facebook/react/pull/32225) by [@Jeremy-Hibiki](https://github.com/Jeremy-Hibiki)
-* remove terser from react-compiler-runtime build [#31326](https://github.com/facebook/react/pull/31326) by [@henryqdineen](https://github.com/henryqdineen)
--- a/compiler/apps/playground/tests/e2e/snapshots/page.spec.ts/compilationMode-all-output.txt
+++ b/compiler/apps/playground/tests/e2e/snapshots/page.spec.ts/compilationMode-all-output.txt
@@ -1,4 +1,5 @@
-import { c as _c } from "react/compiler-runtime"; // @compilationMode:"all"
+import { c as _c } from "react/compiler-runtime"; // 
+        @compilationMode(all)
 function nonReactFn() {
   const $ = _c(1);
   let t0;
--- a/compiler/apps/playground/tests/e2e/snapshots/page.spec.ts/compilationMode-infer-output.txt
+++ b/compiler/apps/playground/tests/e2e/snapshots/page.spec.ts/compilationMode-infer-output.txt
@@ -1,4 +1,4 @@
-// @compilationMode:"infer"
+// @compilationMode(infer)
 function nonReactFn() {
   return {};
 }
--- a/compiler/apps/playground/tests/e2e/snapshots/page.spec.ts/default-config.txt
+++ b/compiler/apps/playground/tests/e2e/snapshots/page.spec.ts/default-config.txt
@@ -1,5 +0,0 @@
-import type { PluginOptions } from 
-'babel-plugin-react-compiler/dist';
-({
-  //compilationMode: "all"
-} satisfies Partial<PluginOptions>);
--- a/compiler/apps/playground/tests/e2e/snapshots/page.spec.ts/disableMemoizationForDebugging-output.txt
+++ b/compiler/apps/playground/tests/e2e/snapshots/page.spec.ts/disableMemoizationForDebugging-output.txt
@@ -1,14 +0,0 @@
-import { c as _c } from "react/compiler-runtime";
-export default function TestComponent(t0) {
-  const $ = _c(2);
-  const { x } = t0;
-  let t1;
-  if ($[0] !== x || true) {
-    t1 = <Button>{x}</Button>;
-    $[0] = x;
-    $[1] = t1;
-  } else {
-    t1 = $[1];
-  }
-  return t1;
-}
--- a/compiler/apps/playground/tests/e2e/page.spec.ts
+++ b/compiler/apps/playground/tests/e2e/page.spec.ts
@@ -5,9 +5,8 @@
 * LICENSE file in the root directory of this source tree.
 */

-import {expect, test, type Page} from '@playwright/test';
+import {expect, test} from '@playwright/test';
 import {encodeStore, type Store} from '../../lib/stores';
-import {defaultConfig} from '../../lib/defaultStore';
 import {format} from 'prettier';

 function isMonacoLoaded(): boolean {
@@ -21,15 +20,6 @@ function formatPrint(data: Array<string>): Promise<string> {
  return format(data.join(''), {parser: 'babel'});
 }

-async function expandConfigs(page: Page): Promise<void> {
-  const expandButton = page.locator('[title="Expand config editor"]');
-  expandButton.click();
-}
-
-const TEST_SOURCE = `export default function TestComponent({ x }) {
-  return <Button>{x}</Button>;
-}`;
-
 const TEST_CASE_INPUTS = [
  {
    name: 'module-scope-use-memo',
@@ -102,7 +92,7 @@ function useFoo(propVal: {+baz: number}) {
  },
  {
    name: 'compilationMode-infer',
-    input: `// @compilationMode:"infer"
+    input: `// @compilationMode(infer)
 function nonReactFn() {
  return {};
 }
@@ -111,7 +101,7 @@ function nonReactFn() {
  },
  {
    name: 'compilationMode-all',
-    input: `// @compilationMode:"all"
+    input: `// @compilationMode(all)
 function nonReactFn() {
  return {};
 }
@@ -131,9 +121,10 @@ test('editor should open successfully', async ({page}) => {

 test('editor should compile from hash successfully', async ({page}) => {
  const store: Store = {
-    source: TEST_SOURCE,
-    config: defaultConfig,
-    showInternals: false,
+    source: `export default function TestComponent({ x }) {
+      return <Button>{x}</Button>;
+    }
+    `,
  };
  const hash = encodeStore(store);
  await page.goto(`/#${hash}`, {waitUntil: 'networkidle'});
@@ -145,7 +136,7 @@ test('editor should compile from hash successfully', async ({page}) => {
    path: 'test-results/01-compiles-from-hash.png',
  });
  const text =
-    (await page.locator('.monaco-editor-output').allInnerTexts()) ?? [];
+    (await page.locator('.monaco-editor').nth(1).allInnerTexts()) ?? [];
  const output = await formatPrint(text);

  expect(output).not.toEqual('');
@@ -154,9 +145,10 @@ test('editor should compile from hash successfully', async ({page}) => {

 test('reset button works', async ({page}) => {
  const store: Store = {
-    source: TEST_SOURCE,
-    config: defaultConfig,
-    showInternals: false,
+    source: `export default function TestComponent({ x }) {
+      return <Button>{x}</Button>;
+    }
+    `,
  };
  const hash = encodeStore(store);
  await page.goto(`/#${hash}`, {waitUntil: 'networkidle'});
@@ -165,171 +157,33 @@ test('reset button works', async ({page}) => {
  // Reset button works
  page.on('dialog', dialog => dialog.accept());
  await page.getByRole('button', {name: 'Reset'}).click();
-  await expandConfigs(page);
-
  await page.screenshot({
    fullPage: true,
    path: 'test-results/02-reset-button-works.png',
  });
  const text =
-    (await page.locator('.monaco-editor-output').allInnerTexts()) ?? [];
+    (await page.locator('.monaco-editor').nth(1).allInnerTexts()) ?? [];
  const output = await formatPrint(text);

-  const configText =
-    (await page.locator('.monaco-editor-config').allInnerTexts()) ?? [];
-  const configOutput = configText.join('');
-
  expect(output).not.toEqual('');
  expect(output).toMatchSnapshot('02-default-output.txt');
-  expect(configOutput).not.toEqual('');
-  expect(configOutput).toMatchSnapshot('default-config.txt');
-});
-
-test('defaults load when only source is in Store', async ({page}) => {
-  // Test for backwards compatibility
-  const partial = {
-    source: TEST_SOURCE,
-  };
-  const hash = encodeStore(partial as Store);
-  await page.goto(`/#${hash}`, {waitUntil: 'networkidle'});
-  await page.waitForFunction(isMonacoLoaded);
-  await expandConfigs(page);
-
-  await page.screenshot({
-    fullPage: true,
-    path: 'test-results/03-missing-defaults.png',
-  });
-
-  // Config editor has default config
-  const configText =
-    (await page.locator('.monaco-editor-config').allInnerTexts()) ?? [];
-  const configOutput = configText.join('');
-
-  expect(configOutput).not.toEqual('');
-  expect(configOutput).toMatchSnapshot('default-config.txt');
-
-  const checkbox = page.locator('label.show-internals');
-  await expect(checkbox).not.toBeChecked();
-  const ssaTab = page.locator('text=SSA');
-  await expect(ssaTab).not.toBeVisible();
-});
-
-test('show internals button toggles correctly', async ({page}) => {
-  await page.goto(`/`, {waitUntil: 'networkidle'});
-  await page.waitForFunction(isMonacoLoaded);
-
-  // show internals should be off
-  const checkbox = page.locator('label.show-internals');
-  await checkbox.click();
-
-  await page.screenshot({
-    fullPage: true,
-    path: 'test-results/04-show-internals-on.png',
-  });
-
-  await expect(checkbox).toBeChecked();
-
-  const ssaTab = page.locator('text=SSA');
-  await expect(ssaTab).toBeVisible();
-});
-
-test('error is displayed when config has syntax error', async ({page}) => {
-  const store: Store = {
-    source: TEST_SOURCE,
-    config: `compilationMode: `,
-    showInternals: false,
-  };
-  const hash = encodeStore(store);
-  await page.goto(`/#${hash}`, {waitUntil: 'networkidle'});
-  await page.waitForFunction(isMonacoLoaded);
-  await expandConfigs(page);
-  await page.screenshot({
-    fullPage: true,
-    path: 'test-results/05-config-syntax-error.png',
-  });
-
-  const text =
-    (await page.locator('.monaco-editor-output').allInnerTexts()) ?? [];
-  const output = text.join('');
-
-  // Remove hidden chars
-  expect(output.replace(/\s+/g, ' ')).toContain('Invalid override format');
-});
-
-test('error is displayed when config has validation error', async ({page}) => {
-  const store: Store = {
-    source: TEST_SOURCE,
-    config: `import type { PluginOptions } from 'babel-plugin-react-compiler/dist';
-
-({
-  compilationMode: "123"
-} satisfies Partial<PluginOptions>);`,
-    showInternals: false,
-  };
-  const hash = encodeStore(store);
-  await page.goto(`/#${hash}`, {waitUntil: 'networkidle'});
-  await page.waitForFunction(isMonacoLoaded);
-  await expandConfigs(page);
-  await page.screenshot({
-    fullPage: true,
-    path: 'test-results/06-config-validation-error.png',
-  });
-
-  const text =
-    (await page.locator('.monaco-editor-output').allInnerTexts()) ?? [];
-  const output = text.join('');
-
-  expect(output.replace(/\s+/g, ' ')).toContain('Unexpected compilationMode');
-});
-
-test('disableMemoizationForDebugging flag works as expected', async ({
-  page,
-}) => {
-  const store: Store = {
-    source: TEST_SOURCE,
-    config: `import type { PluginOptions } from 'babel-plugin-react-compiler/dist';
-
-({
-  environment: {
-    disableMemoizationForDebugging: true
-  }
-} satisfies Partial<PluginOptions>);`,
-    showInternals: false,
-  };
-  const hash = encodeStore(store);
-  await page.goto(`/#${hash}`, {waitUntil: 'networkidle'});
-  await page.waitForFunction(isMonacoLoaded);
-  await expandConfigs(page);
-  await page.screenshot({
-    fullPage: true,
-    path: 'test-results/07-config-disableMemoizationForDebugging-flag.png',
-  });
-
-  const text =
-    (await page.locator('.monaco-editor-output').allInnerTexts()) ?? [];
-  const output = await formatPrint(text);
-
-  expect(output).not.toEqual('');
-  expect(output).toMatchSnapshot('disableMemoizationForDebugging-output.txt');
 });

 TEST_CASE_INPUTS.forEach((t, idx) =>
  test(`playground compiles: ${t.name}`, async ({page}) => {
    const store: Store = {
      source: t.input,
-      config: defaultConfig,
-      showInternals: false,
    };
    const hash = encodeStore(store);
    await page.goto(`/#${hash}`, {waitUntil: 'networkidle'});
    await page.waitForFunction(isMonacoLoaded);
    await page.screenshot({
      fullPage: true,
-      path: `test-results/08-0${idx}-${t.name}.png`,
+      path: `test-results/03-0${idx}-${t.name}.png`,
    });

    const text =
-      (await page.locator('.monaco-editor-output').allInnerTexts()) ?? [];
+      (await page.locator('.monaco-editor').nth(1).allInnerTexts()) ?? [];
    let output: string;
    if (t.noFormat) {
      output = text.join('');
--- a/compiler/apps/playground/app/index.tsx
+++ b/compiler/apps/playground/app/index.tsx
@@ -0,0 +1,56 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+import type {NextPage} from 'next';
+import Head from 'next/head';
+import {SnackbarProvider} from 'notistack';
+import {Editor, Header, StoreProvider} from '../components';
+import MessageSnackbar from '../components/Message';
+
+const Home: NextPage = () => {
+  return (
+    <div className="flex flex-col w-screen h-screen font-light">
+      <Head>
+        <title>
+          {process.env.NODE_ENV === 'development'
+            ? '[DEV] React Compiler Playground'
+            : 'React Compiler Playground'}
+        </title>
+        <meta
+          name="viewport"
+          content="width=device-width, initial-scale=1, maximum-scale=1, user-scalable=0"></meta>
+        <link rel="icon" href="/favicon.ico" />
+        <link rel="manifest" href="/site.webmanifest" />
+        <link
+          rel="preload"
+          href="/fonts/Source-Code-Pro-Regular.woff2"
+          as="font"
+          type="font/woff2"
+          crossOrigin="anonymous"
+        />
+        <link
+          rel="preload"
+          href="/fonts/Optimistic_Display_W_Lt.woff2"
+          as="font"
+          type="font/woff2"
+          crossOrigin="anonymous"
+        />
+      </Head>
+      <StoreProvider>
+        <SnackbarProvider
+          preventDuplicate
+          maxSnack={10}
+          Components={{message: MessageSnackbar}}>
+          <Header />
+          <Editor />
+        </SnackbarProvider>
+      </StoreProvider>
+    </div>
+  );
+};
+
+export default Home;
--- a/compiler/apps/playground/components/AccordionWindow.tsx
+++ b/compiler/apps/playground/components/AccordionWindow.tsx
@@ -1,97 +0,0 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
-import {Resizable} from 're-resizable';
-import React, {useCallback} from 'react';
-
-type TabsRecord = Map<string, React.ReactNode>;
-
-export default function AccordionWindow(props: {
-  defaultTab: string | null;
-  tabs: TabsRecord;
-  tabsOpen: Set<string>;
-  setTabsOpen: (newTab: Set<string>) => void;
-  changedPasses: Set<string>;
-}): React.ReactElement {
-  return (
-    <div className="flex flex-row h-full">
-      {Array.from(props.tabs.keys()).map(name => {
-        return (
-          <AccordionWindowItem
-            name={name}
-            key={name}
-            tabs={props.tabs}
-            tabsOpen={props.tabsOpen}
-            setTabsOpen={props.setTabsOpen}
-            hasChanged={props.changedPasses.has(name)}
-          />
-        );
-      })}
-    </div>
-  );
-}
-
-function AccordionWindowItem({
-  name,
-  tabs,
-  tabsOpen,
-  setTabsOpen,
-  hasChanged,
-}: {
-  name: string;
-  tabs: TabsRecord;
-  tabsOpen: Set<string>;
-  setTabsOpen: (newTab: Set<string>) => void;
-  hasChanged: boolean;
-}): React.ReactElement {
-  const isShow = tabsOpen.has(name);
-
-  const toggleTabs = useCallback(() => {
-    const nextState = new Set(tabsOpen);
-    if (nextState.has(name)) {
-      nextState.delete(name);
-    } else {
-      nextState.add(name);
-    }
-    setTabsOpen(nextState);
-  }, [tabsOpen, name, setTabsOpen]);
-
-  // Replace spaces with non-breaking spaces
-  const displayName = name.replace(/ /g, '\u00A0');
-
-  return (
-    <div key={name} className="flex flex-row">
-      {isShow ? (
-        <Resizable className="border-r" minWidth={550} enable={{right: true}}>
-          <h2
-            title="Minimize tab"
-            aria-label="Minimize tab"
-            onClick={toggleTabs}
-            className={`p-4 duration-150 ease-in border-b cursor-pointer border-grey-200 ${
-              hasChanged ? 'font-bold' : 'font-light'
-            } text-secondary hover:text-link`}>
-            - {displayName}
-          </h2>
-          {tabs.get(name) ?? <div>No output for {name}</div>}
-        </Resizable>
-      ) : (
-        <div className="relative items-center h-full px-1 py-6 align-middle border-r border-grey-200">
-          <button
-            title={`Expand compiler tab: ${name}`}
-            aria-label={`Expand compiler tab: ${name}`}
-            style={{transform: 'rotate(90deg) translate(-50%)'}}
-            onClick={toggleTabs}
-            className={`flex-grow-0 w-5 transition-colors duration-150 ease-in ${
-              hasChanged ? 'font-bold' : 'font-light'
-            } text-secondary hover:text-link`}>
-            {displayName}
-          </button>
-        </div>
-      )}
-    </div>
-  );
-}
--- a/compiler/apps/playground/components/Editor/ConfigEditor.tsx
+++ b/compiler/apps/playground/components/Editor/ConfigEditor.tsx
@@ -1,218 +0,0 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
-import MonacoEditor, {loader, type Monaco} from '@monaco-editor/react';
-import {PluginOptions} from 'babel-plugin-react-compiler';
-import type {editor} from 'monaco-editor';
-import * as monaco from 'monaco-editor';
-import React, {useState, useRef} from 'react';
-import {Resizable} from 're-resizable';
-import {useStore, useStoreDispatch} from '../StoreContext';
-import {monacoOptions} from './monacoOptions';
-import {IconChevron} from '../Icons/IconChevron';
-import prettyFormat from 'pretty-format';
-
-// @ts-expect-error - webpack asset/source loader handles .d.ts files as strings
-import compilerTypeDefs from 'babel-plugin-react-compiler/dist/index.d.ts';
-
-loader.config({monaco});
-
-export default function ConfigEditor({
-  appliedOptions,
-}: {
-  appliedOptions: PluginOptions | null;
-}): React.ReactElement {
-  const [isExpanded, setIsExpanded] = useState(false);
-
-  return (
-    // TODO: Use <Activity> when it is compatible with Monaco: https://github.com/suren-atoyan/monaco-react/issues/753
-    <>
-      <div
-        style={{
-          display: isExpanded ? 'block' : 'none',
-        }}>
-        <ExpandedEditor
-          onToggle={setIsExpanded}
-          appliedOptions={appliedOptions}
-        />
-      </div>
-      <div
-        style={{
-          display: !isExpanded ? 'block' : 'none',
-        }}>
-        <CollapsedEditor onToggle={setIsExpanded} />
-      </div>
-    </>
-  );
-}
-
-function ExpandedEditor({
-  onToggle,
-  appliedOptions,
-}: {
-  onToggle: (expanded: boolean) => void;
-  appliedOptions: PluginOptions | null;
-}): React.ReactElement {
-  const store = useStore();
-  const dispatchStore = useStoreDispatch();
-  const debounceTimerRef = useRef<NodeJS.Timeout | null>(null);
-
-  const handleChange: (value: string | undefined) => void = (
-    value: string | undefined,
-  ) => {
-    if (value === undefined) return;
-
-    if (debounceTimerRef.current) {
-      clearTimeout(debounceTimerRef.current);
-    }
-
-    debounceTimerRef.current = setTimeout(() => {
-      dispatchStore({
-        type: 'updateConfig',
-        payload: {
-          config: value,
-        },
-      });
-    }, 500); // 500ms debounce delay
-  };
-
-  const handleMount: (
-    _: editor.IStandaloneCodeEditor,
-    monaco: Monaco,
-  ) => void = (_, monaco) => {
-    // Add the babel-plugin-react-compiler type definitions to Monaco
-    monaco.languages.typescript.typescriptDefaults.addExtraLib(
-      //@ts-expect-error - compilerTypeDefs is a string
-      compilerTypeDefs,
-      'file:///node_modules/babel-plugin-react-compiler/dist/index.d.ts',
-    );
-    monaco.languages.typescript.typescriptDefaults.setCompilerOptions({
-      target: monaco.languages.typescript.ScriptTarget.Latest,
-      allowNonTsExtensions: true,
-      moduleResolution: monaco.languages.typescript.ModuleResolutionKind.NodeJs,
-      module: monaco.languages.typescript.ModuleKind.ESNext,
-      noEmit: true,
-      strict: false,
-      esModuleInterop: true,
-      allowSyntheticDefaultImports: true,
-      jsx: monaco.languages.typescript.JsxEmit.React,
-    });
-  };
-
-  const formattedAppliedOptions = appliedOptions
-    ? prettyFormat(appliedOptions, {
-        printFunctionName: false,
-        printBasicPrototype: false,
-      })
-    : 'Invalid configs';
-
-  return (
-    <Resizable
-      minWidth={300}
-      maxWidth={600}
-      defaultSize={{width: 350}}
-      enable={{right: true, bottom: false}}>
-      <div className="bg-blue-10 relative h-full flex flex-col !h-[calc(100vh_-_3.5rem)] border border-gray-300">
-        <div
-          className="absolute w-8 h-16 bg-blue-10 rounded-r-full flex items-center justify-center z-[2] cursor-pointer border border-l-0 border-gray-300"
-          title="Minimize config editor"
-          onClick={() => onToggle(false)}
-          style={{
-            top: '50%',
-            marginTop: '-32px',
-            right: '-32px',
-            borderTopLeftRadius: 0,
-            borderBottomLeftRadius: 0,
-          }}>
-          <IconChevron displayDirection="left" className="text-blue-50" />
-        </div>
-
-        <div className="flex-1 flex flex-col m-2 mb-2">
-          <div className="pb-2">
-            <h2 className="inline-block text-blue-50 py-1.5 px-1.5 xs:px-3 sm:px-4 text-sm">
-              Config Overrides
-            </h2>
-          </div>
-          <div className="flex-1 rounded-lg overflow-hidden border border-gray-300">
-            <MonacoEditor
-              path={'config.ts'}
-              language={'typescript'}
-              value={store.config}
-              onMount={handleMount}
-              onChange={handleChange}
-              loading={''}
-              className="monaco-editor-config"
-              options={{
-                ...monacoOptions,
-                lineNumbers: 'off',
-                renderLineHighlight: 'none',
-                overviewRulerBorder: false,
-                overviewRulerLanes: 0,
-                fontSize: 12,
-                scrollBeyondLastLine: false,
-                glyphMargin: false,
-              }}
-            />
-          </div>
-        </div>
-        <div className="flex-1 flex flex-col m-2">
-          <div className="pb-2">
-            <h2 className="inline-block text-blue-50 py-1.5 px-1.5 xs:px-3 sm:px-4 text-sm">
-              Applied Configs
-            </h2>
-          </div>
-          <div className="flex-1 rounded-lg overflow-hidden border border-gray-300">
-            <MonacoEditor
-              path={'applied-config.js'}
-              language={'javascript'}
-              value={formattedAppliedOptions}
-              loading={''}
-              className="monaco-editor-applied-config"
-              options={{
-                ...monacoOptions,
-                lineNumbers: 'off',
-                renderLineHighlight: 'none',
-                overviewRulerBorder: false,
-                overviewRulerLanes: 0,
-                fontSize: 12,
-                scrollBeyondLastLine: false,
-                readOnly: true,
-                glyphMargin: false,
-              }}
-            />
-          </div>
-        </div>
-      </div>
-    </Resizable>
-  );
-}
-
-function CollapsedEditor({
-  onToggle,
-}: {
-  onToggle: (expanded: boolean) => void;
-}): React.ReactElement {
-  return (
-    <div
-      className="w-4 !h-[calc(100vh_-_3.5rem)]"
-      style={{position: 'relative'}}>
-      <div
-        className="absolute w-10 h-16 bg-blue-10 hover:translate-x-2 transition-transform rounded-r-full flex items-center justify-center z-[2] cursor-pointer border border-gray-300"
-        title="Expand config editor"
-        onClick={() => onToggle(true)}
-        style={{
-          top: '50%',
-          marginTop: '-32px',
-          left: '-8px',
-          borderTopLeftRadius: 0,
-          borderBottomLeftRadius: 0,
-        }}>
-        <IconChevron displayDirection="right" className="text-blue-50" />
-      </div>
-    </div>
-  );
-}
--- a/compiler/apps/playground/components/Editor/EditorImpl.tsx
+++ b/compiler/apps/playground/components/Editor/EditorImpl.tsx
@@ -11,22 +11,29 @@ import * as t from '@babel/types';
 import BabelPluginReactCompiler, {
  CompilerError,
  CompilerErrorDetail,
-  CompilerDiagnostic,
  Effect,
-  ErrorCategory,
+  ErrorSeverity,
  parseConfigPragmaForTests,
  ValueKind,
  type Hook,
  PluginOptions,
  CompilerPipelineValue,
  parsePluginOptions,
-  printReactiveFunctionWithOutlined,
-  printFunctionWithOutlined,
-  type LoggerEvent,
-} from 'babel-plugin-react-compiler';
+} from 'babel-plugin-react-compiler/src';
+import clsx from 'clsx';
+import invariant from 'invariant';
+import {useSnackbar} from 'notistack';
 import {useDeferredValue, useMemo} from 'react';
-import {useStore} from '../StoreContext';
-import ConfigEditor from './ConfigEditor';
+import {useMountEffect} from '../../hooks';
+import {defaultStore} from '../../lib/defaultStore';
+import {
+  createMessage,
+  initStoreFromUrlOrLocalStorage,
+  MessageLevel,
+  MessageSource,
+  type Store,
+} from '../../lib/stores';
+import {useStore, useStoreDispatch} from '../StoreContext';
 import Input from './Input';
 import {
  CompilerOutput,
@@ -34,6 +41,8 @@ import {
  default as Output,
  PrintedCompilerPipelineValue,
 } from './Output';
+import {printFunctionWithOutlined} from 'babel-plugin-react-compiler/src/HIR/PrintHIR';
+import {printReactiveFunctionWithOutlined} from 'babel-plugin-react-compiler/src/ReactiveScopes/PrintReactiveFunction';
 import {transformFromAstSync} from '@babel/core';

 function parseInput(
@@ -131,68 +140,9 @@ const COMMON_HOOKS: Array<[string, Hook]> = [
  ],
 ];

-function parseOptions(
-  source: string,
-  mode: 'compiler' | 'linter',
-  configOverrides: string,
-): PluginOptions {
-  // Extract the first line to quickly check for custom test directives
-  const pragma = source.substring(0, source.indexOf('\n'));
-
-  const parsedPragmaOptions = parseConfigPragmaForTests(pragma, {
-    compilationMode: 'infer',
-    environment:
-      mode === 'linter'
-        ? {
-            // enabled in compiler
-            validateRefAccessDuringRender: false,
-            // enabled in linter
-            validateNoSetStateInRender: true,
-            validateNoSetStateInEffects: true,
-            validateNoJSXInTryStatements: true,
-            validateNoImpureFunctionsInRender: true,
-            validateStaticComponents: true,
-            validateNoFreezingKnownMutableFunctions: true,
-            validateNoVoidUseMemo: true,
-          }
-        : {
-            /* use defaults for compiler mode */
-          },
-  });
-
-  // Parse config overrides from config editor
-  let configOverrideOptions: any = {};
-  const configMatch = configOverrides.match(/^\s*import.*?\n\n\((.*)\)/s);
-  if (configOverrides.trim()) {
-    if (configMatch && configMatch[1]) {
-      const configString = configMatch[1].replace(/satisfies.*$/, '').trim();
-      configOverrideOptions = new Function(`return (${configString})`)();
-    } else {
-      throw new Error('Invalid override format');
-    }
-  }
-
-  const opts: PluginOptions = parsePluginOptions({
-    ...parsedPragmaOptions,
-    ...configOverrideOptions,
-    environment: {
-      ...parsedPragmaOptions.environment,
-      ...configOverrideOptions.environment,
-      customHooks: new Map([...COMMON_HOOKS]),
-    },
-  });
-
-  return opts;
-}
-
-function compile(
-  source: string,
-  mode: 'compiler' | 'linter',
-  configOverrides: string,
-): [CompilerOutput, 'flow' | 'typescript', PluginOptions | null] {
+function compile(source: string): [CompilerOutput, 'flow' | 'typescript'] {
  const results = new Map<string, Array<PrintedCompilerPipelineValue>>();
  const error = new CompilerError();
-  const otherErrors: Array<CompilerErrorDetail | CompilerDiagnostic> = [];
  const upsert: (result: PrintedCompilerPipelineValue) => void = result => {
    const entry = results.get(result.name);
    if (Array.isArray(entry)) {
@@ -208,147 +158,136 @@ function compile(
    language = 'typescript';
  }
  let transformOutput;
-
-  let baseOpts: PluginOptions | null = null;
  try {
-    baseOpts = parseOptions(source, mode, configOverrides);
-  } catch (err) {
-    error.details.push(
-      new CompilerErrorDetail({
-        category: ErrorCategory.Config,
-        reason: `Unexpected failure when transforming configs! \n${err}`,
-        loc: null,
-        suggestions: null,
-      }),
-    );
-  }
-  if (baseOpts) {
-    try {
-      const logIR = (result: CompilerPipelineValue): void => {
-        switch (result.kind) {
-          case 'ast': {
-            break;
-          }
-          case 'hir': {
-            upsert({
-              kind: 'hir',
-              fnName: result.value.id,
-              name: result.name,
-              value: printFunctionWithOutlined(result.value),
-            });
-            break;
-          }
-          case 'reactive': {
-            upsert({
-              kind: 'reactive',
-              fnName: result.value.id,
-              name: result.name,
-              value: printReactiveFunctionWithOutlined(result.value),
-            });
-            break;
-          }
-          case 'debug': {
-            upsert({
-              kind: 'debug',
-              fnName: null,
-              name: result.name,
-              value: result.value,
-            });
-            break;
-          }
-          default: {
-            const _: never = result;
-            throw new Error(`Unhandled result ${result}`);
-          }
+    // Extract the first line to quickly check for custom test directives
+    const pragma = source.substring(0, source.indexOf('\n'));
+    const logIR = (result: CompilerPipelineValue): void => {
+      switch (result.kind) {
+        case 'ast': {
+          break;
+        }
+        case 'hir': {
+          upsert({
+            kind: 'hir',
+            fnName: result.value.id,
+            name: result.name,
+            value: printFunctionWithOutlined(result.value),
+          });
+          break;
+        }
+        case 'reactive': {
+          upsert({
+            kind: 'reactive',
+            fnName: result.value.id,
+            name: result.name,
+            value: printReactiveFunctionWithOutlined(result.value),
+          });
+          break;
+        }
+        case 'debug': {
+          upsert({
+            kind: 'debug',
+            fnName: null,
+            name: result.name,
+            value: result.value,
+          });
+          break;
+        }
+        default: {
+          const _: never = result;
+          throw new Error(`Unhandled result ${result}`);
        }
-      };
-      // Add logger options to the parsed options
-      const opts = {
-        ...baseOpts,
-        logger: {
-          debugLogIRs: logIR,
-          logEvent: (_filename: string | null, event: LoggerEvent): void => {
-            if (event.kind === 'CompileError') {
-              otherErrors.push(event.detail);
-            }
-          },
-        },
-      };
-      transformOutput = invokeCompiler(source, language, opts);
-    } catch (err) {
-      /**
-       * error might be an invariant violation or other runtime error
-       * (i.e. object shape that is not CompilerError)
-       */
-      if (err instanceof CompilerError && err.details.length > 0) {
-        error.merge(err);
-      } else {
-        /**
-         * Handle unexpected failures by logging (to get a stack trace)
-         * and reporting
-         */
-        error.details.push(
-          new CompilerErrorDetail({
-            category: ErrorCategory.Invariant,
-            reason: `Unexpected failure when transforming input! \n${err}`,
-            loc: null,
-            suggestions: null,
-          }),
-        );
      }
+    };
+    const parsedOptions = parseConfigPragmaForTests(pragma, {
+      compilationMode: 'infer',
+    });
+    const opts: PluginOptions = parsePluginOptions({
+      ...parsedOptions,
+      environment: {
+        ...parsedOptions.environment,
+        customHooks: new Map([...COMMON_HOOKS]),
+      },
+      logger: {
+        debugLogIRs: logIR,
+        logEvent: () => {},
+      },
+    });
+    transformOutput = invokeCompiler(source, language, opts);
+  } catch (err) {
+    /**
+     * error might be an invariant violation or other runtime error
+     * (i.e. object shape that is not CompilerError)
+     */
+    if (err instanceof CompilerError && err.details.length > 0) {
+      error.details.push(...err.details);
+    } else {
+      /**
+       * Handle unexpected failures by logging (to get a stack trace)
+       * and reporting
+       */
+      console.error(err);
+      error.details.push(
+        new CompilerErrorDetail({
+          severity: ErrorSeverity.Invariant,
+          reason: `Unexpected failure when transforming input! ${err}`,
+          loc: null,
+          suggestions: null,
+        }),
+      );
    }
  }
-  // Only include logger errors if there weren't other errors
-  if (!error.hasErrors() && otherErrors.length !== 0) {
-    otherErrors.forEach(e => error.details.push(e));
-  }
  if (error.hasErrors()) {
-    return [{kind: 'err', results, error}, language, baseOpts];
+    return [{kind: 'err', results, error: error}, language];
  }
-  return [
-    {kind: 'ok', results, transformOutput, errors: error.details},
-    language,
-    baseOpts,
-  ];
+  return [{kind: 'ok', results, transformOutput}, language];
 }

 export default function Editor(): JSX.Element {
  const store = useStore();
  const deferredStore = useDeferredValue(store);
-  const [compilerOutput, language, appliedOptions] = useMemo(
-    () => compile(deferredStore.source, 'compiler', deferredStore.config),
-    [deferredStore.source, deferredStore.config],
-  );
-  const [linterOutput] = useMemo(
-    () => compile(deferredStore.source, 'linter', deferredStore.config),
-    [deferredStore.source, deferredStore.config],
+  const dispatchStore = useStoreDispatch();
+  const {enqueueSnackbar} = useSnackbar();
+  const [compilerOutput, language] = useMemo(
+    () => compile(deferredStore.source),
+    [deferredStore.source],
  );

-  let mergedOutput: CompilerOutput;
-  let errors: Array<CompilerErrorDetail | CompilerDiagnostic>;
-  if (compilerOutput.kind === 'ok') {
-    errors = linterOutput.kind === 'ok' ? [] : linterOutput.error.details;
-    mergedOutput = {
-      ...compilerOutput,
-      errors,
-    };
-  } else {
-    mergedOutput = compilerOutput;
-    errors = compilerOutput.error.details;
-  }
+  useMountEffect(() => {
+    let mountStore: Store;
+    try {
+      mountStore = initStoreFromUrlOrLocalStorage();
+    } catch (e) {
+      invariant(e instanceof Error, 'Only Error may be caught.');
+      enqueueSnackbar(e.message, {
+        variant: 'warning',
+        ...createMessage(
+          'Bad URL - fell back to the default Playground.',
+          MessageLevel.Info,
+          MessageSource.Playground,
+        ),
+      });
+      mountStore = defaultStore;
+    }
+    dispatchStore({
+      type: 'setStore',
+      payload: {store: mountStore},
+    });
+  });
+
  return (
    <>
-      <div className="relative flex top-14">
-        <div className="flex-shrink-0">
-          <ConfigEditor appliedOptions={appliedOptions} />
+      <div className="relative flex basis top-14">
+        <div className={clsx('relative sm:basis-1/4')}>
+          <Input
+            language={language}
+            errors={
+              compilerOutput.kind === 'err' ? compilerOutput.error.details : []
+            }
+          />
        </div>
-        <div className="flex flex-1 min-w-0">
-          <div className="flex-1 min-w-[550px] sm:min-w-0">
-            <Input language={language} errors={errors} />
-          </div>
-          <div className="flex-1 min-w-[550px] sm:min-w-0">
-            <Output store={deferredStore} compilerOutput={mergedOutput} />
-          </div>
+        <div className={clsx('flex sm:flex flex-wrap')}>
+          <Output store={deferredStore} compilerOutput={compilerOutput} />
        </div>
      </div>
    </>
--- a/compiler/apps/playground/components/Editor/Input.tsx
+++ b/compiler/apps/playground/components/Editor/Input.tsx
@@ -6,17 +6,14 @@
 */

 import MonacoEditor, {loader, type Monaco} from '@monaco-editor/react';
-import {
-  CompilerErrorDetail,
-  CompilerDiagnostic,
-} from 'babel-plugin-react-compiler';
+import {CompilerErrorDetail} from 'babel-plugin-react-compiler/src';
 import invariant from 'invariant';
 import type {editor} from 'monaco-editor';
 import * as monaco from 'monaco-editor';
+import {Resizable} from 're-resizable';
 import {useEffect, useState} from 'react';
 import {renderReactCompilerMarkers} from '../../lib/reactCompilerMonacoDiagnostics';
 import {useStore, useStoreDispatch} from '../StoreContext';
-import TabbedWindow from '../TabbedWindow';
 import {monacoOptions} from './monacoOptions';
 // @ts-expect-error TODO: Make TS recognize .d.ts files, in addition to loading them with webpack.
 import React$Types from '../../node_modules/@types/react/index.d.ts';
@@ -24,7 +21,7 @@ import React$Types from '../../node_modules/@types/react/index.d.ts';
 loader.config({monaco});

 type Props = {
-  errors: Array<CompilerErrorDetail | CompilerDiagnostic>;
+  errors: Array<CompilerErrorDetail>;
  language: 'flow' | 'typescript';
 };

@@ -39,13 +36,13 @@ export default function Input({errors, language}: Props): JSX.Element {
    const uri = monaco.Uri.parse(`file:///index.js`);
    const model = monaco.editor.getModel(uri);
    invariant(model, 'Model must exist for the selected input file.');
-    renderReactCompilerMarkers({
-      monaco,
-      model,
-      details: errors,
-      source: store.source,
-    });
-  }, [monaco, errors, store.source]);
+    renderReactCompilerMarkers({monaco, model, details: errors});
+    /**
+     * N.B. that `tabSize` is a model property, not an editor property.
+     * So, the tab size has to be set per model.
+     */
+    model.updateOptions({tabSize: 2});
+  }, [monaco, errors]);

  useEffect(() => {
    /**
@@ -77,11 +74,11 @@ export default function Input({errors, language}: Props): JSX.Element {
    });
  }, [monaco, language]);

-  const handleChange: (value: string | undefined) => void = async value => {
+  const handleChange: (value: string | undefined) => void = value => {
    if (!value) return;

    dispatchStore({
-      type: 'updateSource',
+      type: 'updateFile',
      payload: {
        source: value,
      },
@@ -133,38 +130,30 @@ export default function Input({errors, language}: Props): JSX.Element {
    });
  };

-  const editorContent = (
-    <MonacoEditor
-      path={'index.js'}
-      /**
-       * .js and .jsx files are specified to be TS so that Monaco can actually
-       * check their syntax using its TS language service. They are still JS files
-       * due to their extensions, so TS language features don't work.
-       */
-      language={'javascript'}
-      value={store.source}
-      onMount={handleMount}
-      onChange={handleChange}
-      className="monaco-editor-input"
-      options={monacoOptions}
-      loading={''}
-    />
-  );
-
-  const tabs = new Map([['Input', editorContent]]);
-  const [activeTab, setActiveTab] = useState('Input');
-
  return (
    <div className="relative flex flex-col flex-none border-r border-gray-200">
-      <div className="!h-[calc(100vh_-_3.5rem)]">
-        <div className="flex flex-col h-full">
-          <TabbedWindow
-            tabs={tabs}
-            activeTab={activeTab}
-            onTabChange={setActiveTab}
-          />
-        </div>
-      </div>
+      <Resizable
+        minWidth={650}
+        enable={{right: true}}
+        /**
+         * Restrict MonacoEditor's height, since the config autoLayout:true
+         * will grow the editor to fit within parent element
+         */
+        className="!h-[calc(100vh_-_3.5rem)]">
+        <MonacoEditor
+          path={'index.js'}
+          /**
+           * .js and .jsx files are specified to be TS so that Monaco can actually
+           * check their syntax using its TS language service. They are still JS files
+           * due to their extensions, so TS language features don't work.
+           */
+          language={'javascript'}
+          value={store.source}
+          onMount={handleMount}
+          onChange={handleChange}
+          options={monacoOptions}
+        />
+      </Resizable>
    </div>
  );
 }
--- a/compiler/apps/playground/components/Editor/Output.tsx
+++ b/compiler/apps/playground/components/Editor/Output.tsx
@@ -11,27 +11,19 @@ import {
  InformationCircleIcon,
 } from '@heroicons/react/outline';
 import MonacoEditor, {DiffEditor} from '@monaco-editor/react';
-import {
-  CompilerErrorDetail,
-  CompilerDiagnostic,
-  type CompilerError,
-} from 'babel-plugin-react-compiler';
+import {type CompilerError} from 'babel-plugin-react-compiler/src';
 import parserBabel from 'prettier/plugins/babel';
 import * as prettierPluginEstree from 'prettier/plugins/estree';
 import * as prettier from 'prettier/standalone';
 import {memo, ReactNode, useEffect, useState} from 'react';
 import {type Store} from '../../lib/stores';
-import AccordionWindow from '../AccordionWindow';
 import TabbedWindow from '../TabbedWindow';
 import {monacoOptions} from './monacoOptions';
 import {BabelFileResult} from '@babel/core';
-
 const MemoizedOutput = memo(Output);

 export default MemoizedOutput;

-export const BASIC_OUTPUT_TAB_NAMES = ['Output', 'SourceMap'];
-
 export type PrintedCompilerPipelineValue =
  | {
      kind: 'hir';
@@ -52,7 +44,6 @@ export type CompilerOutput =
      kind: 'ok';
      transformOutput: CompilerTransformOutput;
      results: Map<string, Array<PrintedCompilerPipelineValue>>;
-      errors: Array<CompilerErrorDetail | CompilerDiagnostic>;
    }
  | {
      kind: 'err';
@@ -68,16 +59,12 @@ type Props = {
 async function tabify(
  source: string,
  compilerOutput: CompilerOutput,
-  showInternals: boolean,
 ): Promise<Map<string, ReactNode>> {
  const tabs = new Map<string, React.ReactNode>();
  const reorderedTabs = new Map<string, React.ReactNode>();
  const concattedResults = new Map<string, string>();
  // Concat all top level function declaration results into a single tab for each pass
  for (const [passName, results] of compilerOutput.results) {
-    if (!showInternals && !BASIC_OUTPUT_TAB_NAMES.includes(passName)) {
-      continue;
-    }
    for (const result of results) {
      switch (result.kind) {
        case 'hir': {
@@ -136,36 +123,10 @@ async function tabify(
      parser: transformOutput.language === 'flow' ? 'babel-flow' : 'babel-ts',
      plugins: [parserBabel, prettierPluginEstree],
    });
-
-    let output: string;
-    let language: string;
-    if (compilerOutput.errors.length === 0) {
-      output = code;
-      language = 'javascript';
-    } else {
-      language = 'markdown';
-      output = `
-# Summary
-
-React Compiler compiled this function successfully, but there are lint errors that indicate potential issues with the original code.
-
-## ${compilerOutput.errors.length} Lint Errors
-
-${compilerOutput.errors.map(e => e.printErrorMessage(source, {eslint: false})).join('\n\n')}
-
-## Output
-
-\`\`\`js
-${code}
-\`\`\`
-`.trim();
-    }
-
    reorderedTabs.set(
-      'Output',
+      'JS',
      <TextTabContent
-        output={output}
-        language={language}
+        output={code}
        diff={null}
        showInfoPanel={false}></TextTabContent>,
    );
@@ -181,18 +142,6 @@ ${code}
        </>,
      );
    }
-  } else if (compilerOutput.kind === 'err') {
-    const errors = compilerOutput.error.printErrorMessage(source, {
-      eslint: false,
-    });
-    reorderedTabs.set(
-      'Output',
-      <TextTabContent
-        output={errors}
-        language="markdown"
-        diff={null}
-        showInfoPanel={false}></TextTabContent>,
-    );
  }
  tabs.forEach((tab, name) => {
    reorderedTabs.set(name, tab);
@@ -213,34 +162,17 @@ function getSourceMapUrl(code: string, map: string): string | null {
 }

 function Output({store, compilerOutput}: Props): JSX.Element {
-  const [tabsOpen, setTabsOpen] = useState<Set<string>>(
-    () => new Set(['Output']),
-  );
+  const [tabsOpen, setTabsOpen] = useState<Set<string>>(() => new Set(['JS']));
  const [tabs, setTabs] = useState<Map<string, React.ReactNode>>(
    () => new Map(),
  );
-  const [activeTab, setActiveTab] = useState<string>('Output');
-
-  /*
-   * Update the active tab back to the output or errors tab when the compilation state
-   * changes between success/failure.
-   */
-  const [previousOutputKind, setPreviousOutputKind] = useState(
-    compilerOutput.kind,
-  );
-  if (compilerOutput.kind !== previousOutputKind) {
-    setPreviousOutputKind(compilerOutput.kind);
-    setTabsOpen(new Set(['Output']));
-    setActiveTab('Output');
-  }
-
  useEffect(() => {
-    tabify(store.source, compilerOutput, store.showInternals).then(tabs => {
+    tabify(store.source, compilerOutput).then(tabs => {
      setTabs(tabs);
    });
-  }, [store.source, compilerOutput, store.showInternals]);
+  }, [store.source, compilerOutput]);

-  const changedPasses: Set<string> = new Set(['Output', 'HIR']); // Initial and final passes should always be bold
+  const changedPasses: Set<string> = new Set(['JS', 'HIR']); // Initial and final passes should always be bold
  let lastResult: string = '';
  for (const [passName, results] of compilerOutput.results) {
    for (const result of results) {
@@ -255,24 +187,30 @@ function Output({store, compilerOutput}: Props): JSX.Element {
    }
  }

-  if (!store.showInternals) {
-    return (
-      <TabbedWindow
-        tabs={tabs}
-        activeTab={activeTab}
-        onTabChange={setActiveTab}
-      />
-    );
-  }
-
  return (
-    <AccordionWindow
-      defaultTab={store.showInternals ? 'HIR' : 'Output'}
-      setTabsOpen={setTabsOpen}
-      tabsOpen={tabsOpen}
-      tabs={tabs}
-      changedPasses={changedPasses}
-    />
+    <>
+      <TabbedWindow
+        defaultTab="HIR"
+        setTabsOpen={setTabsOpen}
+        tabsOpen={tabsOpen}
+        tabs={tabs}
+        changedPasses={changedPasses}
+      />
+      {compilerOutput.kind === 'err' ? (
+        <div
+          className="flex flex-wrap absolute bottom-0 bg-white grow border-y border-grey-200 transition-all ease-in"
+          style={{width: 'calc(100vw - 650px)'}}>
+          <div className="w-full p-4 basis-full border-b">
+            <h2>COMPILER ERRORS</h2>
+          </div>
+          <pre
+            className="p-4 basis-full text-red-600 overflow-y-scroll whitespace-pre-wrap"
+            style={{width: 'calc(100vw - 650px)', height: '150px'}}>
+            <code>{compilerOutput.error.toString()}</code>
+          </pre>
+        </div>
+      ) : null}
+    </>
  );
 }

@@ -280,12 +218,10 @@ function TextTabContent({
  output,
  diff,
  showInfoPanel,
-  language,
 }: {
  output: string;
  diff: string | null;
  showInfoPanel: boolean;
-  language: string;
 }): JSX.Element {
  const [diffMode, setDiffMode] = useState(false);
  return (
@@ -324,7 +260,6 @@ function TextTabContent({
        <DiffEditor
          original={diff}
          modified={output}
-          loading={''}
          options={{
            ...monacoOptions,
            readOnly: true,
@@ -337,10 +272,8 @@ function TextTabContent({
        />
      ) : (
        <MonacoEditor
-          language={language ?? 'javascript'}
+          defaultLanguage="javascript"
          value={output}
-          loading={''}
-          className="monaco-editor-output"
          options={{
            ...monacoOptions,
            readOnly: true,
--- a/compiler/apps/playground/components/Editor/monacoOptions.ts
+++ b/compiler/apps/playground/components/Editor/monacoOptions.ts
@@ -28,7 +28,5 @@ export const monacoOptions: Partial<EditorProps['options']> = {

  automaticLayout: true,
  wordWrap: 'on',
-  wrappingIndent: 'same',
-
-  tabSize: 2,
+  wrappingIndent: 'deepIndent',
 };
--- a/compiler/apps/playground/components/Header.tsx
+++ b/compiler/apps/playground/components/Header.tsx
@@ -14,11 +14,10 @@ import {useState} from 'react';
 import {defaultStore} from '../lib/defaultStore';
 import {IconGitHub} from './Icons/IconGitHub';
 import Logo from './Logo';
-import {useStore, useStoreDispatch} from './StoreContext';
+import {useStoreDispatch} from './StoreContext';

 export default function Header(): JSX.Element {
  const [showCheck, setShowCheck] = useState(false);
-  const store = useStore();
  const dispatchStore = useStoreDispatch();
  const {enqueueSnackbar, closeSnackbar} = useSnackbar();

@@ -57,27 +56,6 @@ export default function Header(): JSX.Element {
        <p className="hidden select-none sm:block">React Compiler Playground</p>
      </div>
      <div className="flex items-center text-[15px] gap-4">
-        <div className="flex items-center gap-2">
-          <label className="show-internals relative inline-block w-[34px] h-5">
-            <input
-              type="checkbox"
-              checked={store.showInternals}
-              onChange={() => dispatchStore({type: 'toggleInternals'})}
-              className="absolute opacity-0 cursor-pointer h-full w-full m-0"
-            />
-            <span
-              className={clsx(
-                'absolute inset-0 rounded-full cursor-pointer transition-all duration-250',
-                "before:content-[''] before:absolute before:w-4 before:h-4 before:left-0.5 before:bottom-0.5",
-                'before:bg-white before:rounded-full before:transition-transform before:duration-250',
-                'focus-within:shadow-[0_0_1px_#2196F3]',
-                store.showInternals
-                  ? 'bg-link before:translate-x-3.5'
-                  : 'bg-gray-300',
-              )}></span>
-          </label>
-          <span className="text-secondary">Show Internals</span>
-        </div>
        <button
          title="Reset Playground"
          aria-label="Reset Playground"
--- a/compiler/apps/playground/components/Icons/IconChevron.tsx
+++ b/compiler/apps/playground/components/Icons/IconChevron.tsx
@@ -1,41 +0,0 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
-import {memo} from 'react';
-
-export const IconChevron = memo<
-  JSX.IntrinsicElements['svg'] & {
-    /**
-     * The direction the arrow should point.
-     */
-    displayDirection: 'right' | 'left';
-  }
->(function IconChevron({className, displayDirection, ...props}) {
-  const rotationClass =
-    displayDirection === 'left' ? 'rotate-90' : '-rotate-90';
-  const classes = className ? `${rotationClass} ${className}` : rotationClass;
-
-  return (
-    <svg
-      className={classes}
-      xmlns="http://www.w3.org/2000/svg"
-      width="20"
-      height="20"
-      viewBox="0 0 20 20"
-      {...props}>
-      <g fill="none" fillRule="evenodd" transform="translate(-446 -398)">
-        <path
-          fill="currentColor"
-          fillRule="nonzero"
-          d="M95.8838835,240.366117 C95.3957281,239.877961 94.6042719,239.877961 94.1161165,240.366117 C93.6279612,240.854272 93.6279612,241.645728 94.1161165,242.133883 L98.6161165,246.633883 C99.1042719,247.122039 99.8957281,247.122039 100.383883,246.633883 L104.883883,242.133883 C105.372039,241.645728 105.372039,240.854272 104.883883,240.366117 C104.395728,239.877961 103.604272,239.877961 103.116117,240.366117 L99.5,243.982233 L95.8838835,240.366117 Z"
-          transform="translate(356.5 164.5)"
-        />
-        <polygon points="446 418 466 418 466 398 446 398" />
-      </g>
-    </svg>
-  );
-});
--- a/compiler/apps/playground/components/StoreContext.tsx
+++ b/compiler/apps/playground/components/StoreContext.tsx
@@ -6,14 +6,10 @@
 */

 import type {Dispatch, ReactNode} from 'react';
-import {useState, useEffect, useReducer} from 'react';
+import {useEffect, useReducer} from 'react';
 import createContext from '../lib/createContext';
-import {emptyStore, defaultStore} from '../lib/defaultStore';
-import {
-  saveStore,
-  initStoreFromUrlOrLocalStorage,
-  type Store,
-} from '../lib/stores';
+import {emptyStore} from '../lib/defaultStore';
+import {saveStore, type Store} from '../lib/stores';

 const StoreContext = createContext<Store>();

@@ -34,20 +30,6 @@ export const useStoreDispatch = StoreDispatchContext.useContext;
 */
 export function StoreProvider({children}: {children: ReactNode}): JSX.Element {
  const [store, dispatch] = useReducer(storeReducer, emptyStore);
-  const [isPageReady, setIsPageReady] = useState<boolean>(false);
-
-  useEffect(() => {
-    let mountStore: Store;
-    try {
-      mountStore = initStoreFromUrlOrLocalStorage();
-    } catch (e) {
-      console.error('Failed to initialize store from URL or local storage', e);
-      mountStore = defaultStore;
-    }
-    dispatch({type: 'setStore', payload: {store: mountStore}});
-    setIsPageReady(true);
-  }, []);
-
  useEffect(() => {
    if (store !== emptyStore) {
      saveStore(store);
@@ -57,7 +39,7 @@ export function StoreProvider({children}: {children: ReactNode}): JSX.Element {
  return (
    <StoreContext.Provider value={store}>
      <StoreDispatchContext.Provider value={dispatch}>
-        {isPageReady ? children : null}
+        {children}
      </StoreDispatchContext.Provider>
    </StoreContext.Provider>
  );
@@ -71,19 +53,10 @@ type ReducerAction =
      };
    }
  | {
-      type: 'updateSource';
+      type: 'updateFile';
      payload: {
        source: string;
      };
-    }
-  | {
-      type: 'updateConfig';
-      payload: {
-        config: string;
-      };
-    }
-  | {
-      type: 'toggleInternals';
    };

 function storeReducer(store: Store, action: ReducerAction): Store {
@@ -92,28 +65,13 @@ function storeReducer(store: Store, action: ReducerAction): Store {
      const newStore = action.payload.store;
      return newStore;
    }
-    case 'updateSource': {
-      const source = action.payload.source;
+    case 'updateFile': {
+      const {source} = action.payload;
      const newStore = {
        ...store,
        source,
      };
      return newStore;
    }
-    case 'updateConfig': {
-      const config = action.payload.config;
-      const newStore = {
-        ...store,
-        config,
-      };
-      return newStore;
-    }
-    case 'toggleInternals': {
-      const newStore = {
-        ...store,
-        showInternals: !store.showInternals,
-      };
-      return newStore;
-    }
  }
 }
--- a/compiler/apps/playground/components/TabbedWindow.tsx
+++ b/compiler/apps/playground/components/TabbedWindow.tsx
@@ -4,40 +4,103 @@
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 */
-import React from 'react';
-import clsx from 'clsx';

-export default function TabbedWindow({
-  tabs,
-  activeTab,
-  onTabChange,
-}: {
-  tabs: Map<string, React.ReactNode>;
-  activeTab: string;
-  onTabChange: (tab: string) => void;
+import {Resizable} from 're-resizable';
+import React, {useCallback} from 'react';
+
+type TabsRecord = Map<string, React.ReactNode>;
+
+export default function TabbedWindow(props: {
+  defaultTab: string | null;
+  tabs: TabsRecord;
+  tabsOpen: Set<string>;
+  setTabsOpen: (newTab: Set<string>) => void;
+  changedPasses: Set<string>;
 }): React.ReactElement {
+  if (props.tabs.size === 0) {
+    return (
+      <div
+        className="flex items-center justify-center"
+        style={{width: 'calc(100vw - 650px)'}}>
+        No compiler output detected, see errors below
+      </div>
+    );
+  }
  return (
-    <div className="flex flex-col h-full max-w-full">
-      <div className="flex p-2 flex-shrink-0">
-        {Array.from(tabs.keys()).map(tab => {
-          const isActive = activeTab === tab;
-          return (
-            <button
-              key={tab}
-              onClick={() => onTabChange(tab)}
-              className={clsx(
-                'active:scale-95 transition-transform py-1.5 px-1.5 xs:px-3 sm:px-4 rounded-full text-sm',
-                !isActive && 'hover:bg-primary/5',
-                isActive && 'bg-highlight text-link',
-              )}>
-              {tab}
-            </button>
-          );
-        })}
-      </div>
-      <div className="flex-1 overflow-hidden w-full h-full">
-        {tabs.get(activeTab)}
-      </div>
+    <div className="flex flex-row">
+      {Array.from(props.tabs.keys()).map(name => {
+        return (
+          <TabbedWindowItem
+            name={name}
+            key={name}
+            tabs={props.tabs}
+            tabsOpen={props.tabsOpen}
+            setTabsOpen={props.setTabsOpen}
+            hasChanged={props.changedPasses.has(name)}
+          />
+        );
+      })}
+    </div>
+  );
+}
+
+function TabbedWindowItem({
+  name,
+  tabs,
+  tabsOpen,
+  setTabsOpen,
+  hasChanged,
+}: {
+  name: string;
+  tabs: TabsRecord;
+  tabsOpen: Set<string>;
+  setTabsOpen: (newTab: Set<string>) => void;
+  hasChanged: boolean;
+}): React.ReactElement {
+  const isShow = tabsOpen.has(name);
+
+  const toggleTabs = useCallback(() => {
+    const nextState = new Set(tabsOpen);
+    if (nextState.has(name)) {
+      nextState.delete(name);
+    } else {
+      nextState.add(name);
+    }
+    setTabsOpen(nextState);
+  }, [tabsOpen, name, setTabsOpen]);
+
+  // Replace spaces with non-breaking spaces
+  const displayName = name.replace(/ /g, '\u00A0');
+
+  return (
+    <div key={name} className="flex flex-row">
+      {isShow ? (
+        <Resizable className="border-r" minWidth={550} enable={{right: true}}>
+          <h2
+            title="Minimize tab"
+            aria-label="Minimize tab"
+            onClick={toggleTabs}
+            className={`p-4 duration-150 ease-in border-b cursor-pointer border-grey-200 ${
+              hasChanged ? 'font-bold' : 'font-light'
+            } text-secondary hover:text-link`}>
+            - {displayName}
+          </h2>
+          {tabs.get(name) ?? <div>No output for {name}</div>}
+        </Resizable>
+      ) : (
+        <div className="relative items-center h-full px-1 py-6 align-middle border-r border-grey-200">
+          <button
+            title={`Expand compiler tab: ${name}`}
+            aria-label={`Expand compiler tab: ${name}`}
+            style={{transform: 'rotate(90deg) translate(-50%)'}}
+            onClick={toggleTabs}
+            className={`flex-grow-0 w-5 transition-colors duration-150 ease-in ${
+              hasChanged ? 'font-bold' : 'font-light'
+            } text-secondary hover:text-link`}>
+            {displayName}
+          </button>
+        </div>
+      )}
    </div>
  );
 }
--- a/compiler/apps/playground/lib/defaultStore.ts
+++ b/compiler/apps/playground/lib/defaultStore.ts
@@ -13,21 +13,10 @@ export default function MyApp() {
 }
 `;

-export const defaultConfig = `\
-import type { PluginOptions } from 'babel-plugin-react-compiler/dist';
-
-({
-  //compilationMode: "all"
-} satisfies PluginOptions);`;
-
 export const defaultStore: Store = {
  source: index,
-  config: defaultConfig,
-  showInternals: false,
 };

 export const emptyStore: Store = {
  source: '',
-  config: '',
-  showInternals: false,
 };
--- a/compiler/apps/playground/lib/reactCompilerMonacoDiagnostics.ts
+++ b/compiler/apps/playground/lib/reactCompilerMonacoDiagnostics.ts
@@ -7,10 +7,9 @@

 import {Monaco} from '@monaco-editor/react';
 import {
-  CompilerDiagnostic,
  CompilerErrorDetail,
  ErrorSeverity,
-} from 'babel-plugin-react-compiler';
+} from 'babel-plugin-react-compiler/src';
 import {MarkerSeverity, type editor} from 'monaco-editor';

 function mapReactCompilerSeverityToMonaco(
@@ -26,46 +25,38 @@ function mapReactCompilerSeverityToMonaco(
 }

 function mapReactCompilerDiagnosticToMonacoMarker(
-  detail: CompilerErrorDetail | CompilerDiagnostic,
+  detail: CompilerErrorDetail,
  monaco: Monaco,
-  source: string,
 ): editor.IMarkerData | null {
-  const loc = detail.primaryLocation();
-  if (loc == null || typeof loc === 'symbol') {
+  if (detail.loc == null || typeof detail.loc === 'symbol') {
    return null;
  }
  const severity = mapReactCompilerSeverityToMonaco(detail.severity, monaco);
-  let message = detail.printErrorMessage(source, {eslint: true});
+  let message = detail.printErrorMessage();
  return {
    severity,
    message,
-    startLineNumber: loc.start.line,
-    startColumn: loc.start.column + 1,
-    endLineNumber: loc.end.line,
-    endColumn: loc.end.column + 1,
+    startLineNumber: detail.loc.start.line,
+    startColumn: detail.loc.start.column + 1,
+    endLineNumber: detail.loc.end.line,
+    endColumn: detail.loc.end.column + 1,
  };
 }

 type ReactCompilerMarkerConfig = {
  monaco: Monaco;
  model: editor.ITextModel;
-  details: Array<CompilerErrorDetail | CompilerDiagnostic>;
-  source: string;
+  details: Array<CompilerErrorDetail>;
 };
 let decorations: Array<string> = [];
 export function renderReactCompilerMarkers({
  monaco,
  model,
  details,
-  source,
 }: ReactCompilerMarkerConfig): void {
-  const markers: Array<editor.IMarkerData> = [];
+  let markers = [];
  for (const detail of details) {
-    const marker = mapReactCompilerDiagnosticToMonacoMarker(
-      detail,
-      monaco,
-      source,
-    );
+    const marker = mapReactCompilerDiagnosticToMonacoMarker(detail, monaco);
    if (marker == null) {
      continue;
    }
--- a/compiler/apps/playground/lib/stores/store.ts
+++ b/compiler/apps/playground/lib/stores/store.ts
@@ -10,20 +10,18 @@ import {
  compressToEncodedURIComponent,
  decompressFromEncodedURIComponent,
 } from 'lz-string';
-import {defaultStore, defaultConfig} from '../defaultStore';
+import {defaultStore} from '../defaultStore';

 /**
 * Global Store for Playground
 */
 export interface Store {
  source: string;
-  config: string;
-  showInternals: boolean;
 }
 export function encodeStore(store: Store): string {
  return compressToEncodedURIComponent(JSON.stringify(store));
 }
-export function decodeStore(hash: string): any {
+export function decodeStore(hash: string): Store {
  return JSON.parse(decompressFromEncodedURIComponent(hash));
 }

@@ -64,14 +62,8 @@ export function initStoreFromUrlOrLocalStorage(): Store {
   */
  if (!encodedSource) return defaultStore;

-  const raw: any = decodeStore(encodedSource);
+  const raw = decodeStore(encodedSource);

  invariant(isValidStore(raw), 'Invalid Store');
-
-  // Make sure all properties are populated
-  return {
-    source: raw.source,
-    config: 'config' in raw && raw['config'] ? raw.config : defaultConfig,
-    showInternals: 'showInternals' in raw ? raw.showInternals : false,
-  };
+  return raw;
 }
--- a/compiler/apps/playground/next-env.d.ts
+++ b/compiler/apps/playground/next-env.d.ts
@@ -1,6 +1,5 @@
 /// <reference types="next" />
 /// <reference types="next/image-types/global" />
-import "./.next/types/routes.d.ts";

 // NOTE: This file should not be edited
 // see https://nextjs.org/docs/app/api-reference/config/typescript for more information.
--- a/compiler/apps/playground/package.json
+++ b/compiler/apps/playground/package.json
@@ -4,7 +4,7 @@
  "private": true,
  "scripts": {
    "dev": "cd ../.. && concurrently --kill-others -n compiler,runtime,playground \"yarn workspace babel-plugin-react-compiler run watch\" \"yarn workspace react-compiler-runtime run watch\" \"wait-on packages/babel-plugin-react-compiler/dist/index.js && cd apps/playground && NODE_ENV=development next dev\"",
-    "build:compiler": "cd ../.. && concurrently -n compiler,runtime \"yarn workspace babel-plugin-react-compiler run build --dts\" \"yarn workspace react-compiler-runtime run build\"",
+    "build:compiler": "cd ../.. && concurrently -n compiler,runtime \"yarn workspace babel-plugin-react-compiler run build\" \"yarn workspace react-compiler-runtime run build\"",
    "build": "yarn build:compiler && next build",
    "postbuild": "node ./scripts/downloadFonts.js",
    "preinstall": "cd ../.. && yarn install --frozen-lockfile",
@@ -27,37 +27,33 @@
    "@babel/types": "7.26.3",
    "@heroicons/react": "^1.0.6",
    "@monaco-editor/react": "^4.4.6",
-    "@playwright/test": "^1.51.1",
+    "@playwright/test": "^1.42.1",
    "@use-gesture/react": "^10.2.22",
    "hermes-eslint": "^0.25.0",
    "hermes-parser": "^0.25.0",
    "invariant": "^2.2.4",
    "lz-string": "^1.5.0",
    "monaco-editor": "^0.52.0",
-    "next": "15.6.0-canary.7",
+    "next": "^15.2.0-canary.64",
    "notistack": "^3.0.0-alpha.7",
    "prettier": "^3.3.3",
    "pretty-format": "^29.3.1",
    "re-resizable": "^6.9.16",
-    "react": "19.1.1",
-    "react-dom": "19.1.1"
+    "react": "^19.0.0",
+    "react-dom": "^19.0.0"
  },
  "devDependencies": {
    "@types/node": "18.11.9",
-    "@types/react": "19.1.13",
-    "@types/react-dom": "19.1.9",
+    "@types/react": "^19.0.0",
+    "@types/react-dom": "^19.0.0",
    "autoprefixer": "^10.4.13",
    "clsx": "^1.2.1",
    "concurrently": "^7.4.0",
    "eslint": "^8.28.0",
-    "eslint-config-next": "15.5.2",
+    "eslint-config-next": "^15.0.1",
    "monaco-editor-webpack-plugin": "^7.1.0",
    "postcss": "^8.4.31",
    "tailwindcss": "^3.2.4",
    "wait-on": "^7.2.0"
-  },
-  "resolutions": {
-    "@types/react": "19.1.12",
-    "@types/react-dom": "19.1.9"
  }
 }
--- a/compiler/apps/playground/playwright.config.js
+++ b/compiler/apps/playground/playwright.config.js
@@ -55,16 +55,12 @@ export default defineConfig({
    // contextOptions: {
    //   ignoreHTTPSErrors: true,
    // },
-    viewport: {width: 1920, height: 1080},
  },

  projects: [
    {
      name: 'chromium',
-      use: {
-        ...devices['Desktop Chrome'],
-        viewport: {width: 1920, height: 1080},
-      },
+      use: {...devices['Desktop Chrome']},
    },
    // {
    //   name: 'Desktop Firefox',
--- a/compiler/apps/playground/scripts/link-compiler.sh
+++ b/compiler/apps/playground/scripts/link-compiler.sh
@@ -8,8 +8,8 @@ set -eo pipefail

 HERE=$(pwd)

-cd ../../packages/react-compiler-runtime && yarn --silent link && cd "$HERE"
-cd ../../packages/babel-plugin-react-compiler && yarn --silent link && cd "$HERE"
+cd ../../packages/react-compiler-runtime && yarn --silent link && cd $HERE
+cd ../../packages/babel-plugin-react-compiler && yarn --silent link && cd $HERE

 yarn --silent link babel-plugin-react-compiler
 yarn --silent link react-compiler-runtime
--- a/compiler/apps/playground/tsconfig.json
+++ b/compiler/apps/playground/tsconfig.json
@@ -6,9 +6,6 @@
      "dom.iterable",
      "esnext"
    ],
-    "types": [
-      "react/experimental"
-    ],
    "allowJs": true,
    "skipLibCheck": true,
    "strict": true,
@@ -19,7 +16,7 @@
    "moduleResolution": "node",
    "resolveJsonModule": true,
    "isolatedModules": true,
-    "jsx": "react-jsx",
+    "jsx": "preserve",
    "incremental": true,
    "plugins": [
      {
--- a/compiler/apps/playground/yarn.lock
+++ b/compiler/apps/playground/yarn.lock
--- a/compiler/package.json
+++ b/compiler/package.json
@@ -19,8 +19,7 @@
    "test": "yarn workspaces run test",
    "snap": "yarn workspace babel-plugin-react-compiler run snap",
    "snap:build": "yarn workspace snap run build",
-    "npm:publish": "node scripts/release/publish",
-    "eslint-docs": "yarn workspace babel-plugin-react-compiler build && node scripts/build-eslint-docs.js"
+    "npm:publish": "node scripts/release/publish"
  },
  "dependencies": {
    "fs-extra": "^4.0.2",
@@ -38,7 +37,7 @@
    "prettier": "^3.3.3",
    "prettier-plugin-hermes-parser": "^0.26.0",
    "prompt-promise": "^1.0.3",
-    "rimraf": "^6.0.1",
+    "rimraf": "^5.0.10",
    "to-fast-properties": "^2.0.0",
    "tsup": "^8.4.0",
    "typescript": "^5.4.3",
@@ -46,6 +45,7 @@
    "yargs": "^17.7.2"
  },
  "resolutions": {
+    "rimraf": "5.0.10",
    "@babel/types": "7.26.3"
  },
  "packageManager": "yarn@1.22.22"
--- a/compiler/packages/babel-plugin-react-compiler/package.json
+++ b/compiler/packages/babel-plugin-react-compiler/package.json
@@ -12,12 +12,12 @@
    "build": "rimraf dist && tsup",
    "test": "./scripts/link-react-compiler-runtime.sh && yarn snap:ci",
    "jest": "yarn build && ts-node node_modules/.bin/jest",
-    "snap": "yarn workspace snap run snap",
+    "snap": "node ../snap/dist/main.js",
    "snap:build": "yarn workspace snap run build",
    "snap:ci": "yarn snap:build && yarn snap",
    "ts:analyze-trace": "scripts/ts-analyze-trace.sh",
    "lint": "yarn eslint src",
-    "watch": "yarn build --dts --watch"
+    "watch": "yarn build --watch"
  },
  "dependencies": {
    "@babel/types": "^7.26.0"
--- a/compiler/packages/babel-plugin-react-compiler/scripts/jest/e2e-forget.config.js
+++ b/compiler/packages/babel-plugin-react-compiler/scripts/jest/e2e-forget.config.js
@@ -7,4 +7,7 @@

 const makeE2EConfig = require('../jest/makeE2EConfig');

-module.exports = makeE2EConfig('e2e with forget', true);
+const config = makeE2EConfig('e2e with forget', true);
+config.setupFilesAfterEnv = ['<rootDir>/../scripts/jest/setupEnvE2E.js'];
+
+module.exports = config;
--- a/compiler/packages/babel-plugin-react-compiler/scripts/jest/makeTransform.ts
+++ b/compiler/packages/babel-plugin-react-compiler/scripts/jest/makeTransform.ts
@@ -5,16 +5,19 @@
 * LICENSE file in the root directory of this source tree.
 */

+import {jsx} from '@babel/plugin-syntax-jsx';
 import babelJest from 'babel-jest';
-import {
-  validateEnvironmentConfig,
-  EnvironmentConfig,
-} from 'babel-plugin-react-compiler';
+import {compile} from 'babel-plugin-react-compiler';
 import {execSync} from 'child_process';

 import type {NodePath, Visitor} from '@babel/traverse';
-import type {CallExpression} from '@babel/types';
-import BabelPluginReactCompiler from 'babel-plugin-react-compiler';
+import type {CallExpression, FunctionDeclaration} from '@babel/types';
+import * as t from '@babel/types';
+import {
+  EnvironmentConfig,
+  validateEnvironmentConfig,
+} from 'babel-plugin-react-compiler';
+import {basename} from 'path';

 /**
 * -- IMPORTANT --
@@ -25,19 +28,10 @@ import BabelPluginReactCompiler from 'babel-plugin-react-compiler';
 const e2eTransformerCacheKey = 1;
 const forgetOptions: EnvironmentConfig = validateEnvironmentConfig({
  enableAssumeHooksFollowRulesOfReact: true,
+  enableFunctionOutlining: false,
 });
 const debugMode = process.env['DEBUG_FORGET_COMPILER'] != null;

-const compilerCacheKey = execSync(
-  'yarn --silent --cwd ../.. hash packages/babel-plugin-react-compiler/dist',
-)
-  .toString()
-  .trim();
-
-if (debugMode) {
-  console.log('cachebreaker', compilerCacheKey);
-}
-
 module.exports = (useForget: boolean) => {
  function createTransformer() {
    return babelJest.createTransformer({
@@ -48,14 +42,15 @@ module.exports = (useForget: boolean) => {
          plugins: [
            useForget
              ? [
-                  BabelPluginReactCompiler,
+                  ReactForgetFunctionTransform,
                  {
-                    environment: forgetOptions,
                    /*
                     * Jest hashes the babel config as a cache breaker.
                     * (see https://github.com/jestjs/jest/blob/v29.6.2/packages/babel-jest/src/index.ts#L84)
                     */
-                    compilerCacheKey,
+                    compilerCacheKey: execSync(
+                      'yarn --silent --cwd ../.. hash packages/babel-plugin-react-compiler/dist',
+                    ).toString(),
                    transformOptionsCacheKey: forgetOptions,
                    e2eTransformerCacheKey,
                  },
@@ -110,3 +105,103 @@ module.exports = (useForget: boolean) => {
    createTransformer,
  };
 };
+
+// Mostly copied from react/scripts/babel/transform-forget.js
+function isReactComponentLike(fn: NodePath<FunctionDeclaration>): boolean {
+  let isReactComponent = false;
+  let hasNoUseForgetDirective = false;
+
+  /*
+   * React components start with an upper case letter,
+   * React hooks start with `use`
+   */
+  if (
+    fn.node.id == null ||
+    (fn.node.id.name[0].toUpperCase() !== fn.node.id.name[0] &&
+      !/^use[A-Z0-9]/.test(fn.node.id.name))
+  ) {
+    return false;
+  }
+
+  fn.traverse({
+    DirectiveLiteral(path) {
+      if (path.node.value === 'use no forget') {
+        hasNoUseForgetDirective = true;
+      }
+    },
+
+    JSX(path) {
+      // Is there is a JSX node created in the current function context?
+      if (path.scope.getFunctionParent()?.path.node === fn.node) {
+        isReactComponent = true;
+      }
+    },
+
+    CallExpression(path) {
+      // Is there hook usage?
+      if (
+        path.node.callee.type === 'Identifier' &&
+        !/^use[A-Z0-9]/.test(path.node.callee.name)
+      ) {
+        isReactComponent = true;
+      }
+    },
+  });
+
+  if (hasNoUseForgetDirective) {
+    return false;
+  }
+
+  return isReactComponent;
+}
+
+function ReactForgetFunctionTransform() {
+  const compiledFns = new Set();
+  const visitor = {
+    FunctionDeclaration(fn: NodePath<FunctionDeclaration>, state: any): void {
+      if (compiledFns.has(fn.node)) {
+        return;
+      }
+
+      if (!isReactComponentLike(fn)) {
+        return;
+      }
+      if (debugMode) {
+        const filename = basename(state.file.opts.filename);
+        if (fn.node.loc && fn.node.id) {
+          console.log(
+            ` Compiling ${filename}:${fn.node.loc.start.line}:${fn.node.loc.start.column}  ${fn.node.id.name}`,
+          );
+        } else {
+          console.log(` Compiling ${filename} ${fn.node.id?.name}`);
+        }
+      }
+
+      const compiled = compile(
+        fn,
+        forgetOptions,
+        'Other',
+        '_c',
+        null,
+        null,
+        null,
+      );
+      compiledFns.add(compiled);
+
+      const fun = t.functionDeclaration(
+        compiled.id,
+        compiled.params,
+        compiled.body,
+        compiled.generator,
+        compiled.async,
+      );
+      fn.replaceWith(fun);
+      fn.skip();
+    },
+  };
+  return {
+    name: 'react-forget-e2e',
+    inherits: jsx,
+    visitor,
+  };
+}
--- a/compiler/packages/babel-plugin-react-compiler/scripts/jest/setupEnvE2E.js
+++ b/compiler/packages/babel-plugin-react-compiler/scripts/jest/setupEnvE2E.js
@@ -0,0 +1,16 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+const ReactCompilerRuntime = require('react/compiler-runtime');
+
+/*
+ * Our e2e babel transform currently only compiles functions, not programs.
+ * As a result, our e2e transpiled code does not contain an import for the
+ * memo cache function. As a temporary hack, we add a `_c` global, which is
+ * the name that is used for the import by default.
+ */
+globalThis._c = ReactCompilerRuntime.c;
--- a/compiler/packages/babel-plugin-react-compiler/src/Babel/BabelPlugin.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/Babel/BabelPlugin.ts
@@ -11,8 +11,6 @@ import {
  injectReanimatedFlag,
  pipelineUsesReanimatedPlugin,
 } from '../Entrypoint/Reanimated';
-import validateNoUntransformedReferences from '../Entrypoint/ValidateNoUntransformedReferences';
-import {CompilerError} from '..';

 const ENABLE_REACT_COMPILER_TIMINGS =
  process.env['ENABLE_REACT_COMPILER_TIMINGS'] === '1';
@@ -35,58 +33,44 @@ export default function BabelPluginReactCompiler(
       */
      Program: {
        enter(prog, pass): void {
-          try {
-            const filename = pass.filename ?? 'unknown';
-            if (ENABLE_REACT_COMPILER_TIMINGS === true) {
-              performance.mark(`${filename}:start`, {
-                detail: 'BabelPlugin:Program:start',
-              });
-            }
-            let opts = parsePluginOptions(pass.opts);
-            const isDev =
-              (typeof __DEV__ !== 'undefined' && __DEV__ === true) ||
-              process.env['NODE_ENV'] === 'development';
-            if (
-              opts.enableReanimatedCheck === true &&
-              pipelineUsesReanimatedPlugin(pass.file.opts.plugins)
-            ) {
-              opts = injectReanimatedFlag(opts);
-            }
-            if (
-              opts.environment.enableResetCacheOnSourceFileChanges !== false &&
-              isDev
-            ) {
-              opts = {
-                ...opts,
-                environment: {
-                  ...opts.environment,
-                  enableResetCacheOnSourceFileChanges: true,
-                },
-              };
-            }
-            const result = compileProgram(prog, {
-              opts,
-              filename: pass.filename ?? null,
-              comments: pass.file.ast.comments ?? [],
-              code: pass.file.code,
+          const filename = pass.filename ?? 'unknown';
+          if (ENABLE_REACT_COMPILER_TIMINGS === true) {
+            performance.mark(`${filename}:start`, {
+              detail: 'BabelPlugin:Program:start',
+            });
+          }
+          let opts = parsePluginOptions(pass.opts);
+          const isDev =
+            (typeof __DEV__ !== 'undefined' && __DEV__ === true) ||
+            process.env['NODE_ENV'] === 'development';
+          if (
+            opts.enableReanimatedCheck === true &&
+            pipelineUsesReanimatedPlugin(pass.file.opts.plugins)
+          ) {
+            opts = injectReanimatedFlag(opts);
+          }
+          if (
+            opts.environment.enableResetCacheOnSourceFileChanges !== false &&
+            isDev
+          ) {
+            opts = {
+              ...opts,
+              environment: {
+                ...opts.environment,
+                enableResetCacheOnSourceFileChanges: true,
+              },
+            };
+          }
+          compileProgram(prog, {
+            opts,
+            filename: pass.filename ?? null,
+            comments: pass.file.ast.comments ?? [],
+            code: pass.file.code,
+          });
+          if (ENABLE_REACT_COMPILER_TIMINGS === true) {
+            performance.mark(`${filename}:end`, {
+              detail: 'BabelPlugin:Program:end',
            });
-            validateNoUntransformedReferences(
-              prog,
-              pass.filename ?? null,
-              opts.logger,
-              opts.environment,
-              result,
-            );
-            if (ENABLE_REACT_COMPILER_TIMINGS === true) {
-              performance.mark(`${filename}:end`, {
-                detail: 'BabelPlugin:Program:end',
-              });
-            }
-          } catch (e) {
-            if (e instanceof CompilerError) {
-              throw e.withPrintedMessage(pass.file.code, {eslint: false});
-            }
-            throw e;
          }
        },
        exit(_, pass): void {
--- a/compiler/packages/babel-plugin-react-compiler/src/Babel/RunReactCompilerBabelPlugin.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/Babel/RunReactCompilerBabelPlugin.ts
@@ -17,7 +17,7 @@ export function runBabelPluginReactCompiler(
  text: string,
  file: string,
  language: 'flow' | 'typescript',
-  options: PluginOptions | null,
+  options: Partial<PluginOptions> | null,
  includeAst: boolean = false,
 ): BabelCore.BabelFileResult {
  const ast = BabelParser.parse(text, {
--- a/compiler/packages/babel-plugin-react-compiler/src/CompilerError.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/CompilerError.ts
--- a/compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Gating.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Gating.ts
@@ -7,136 +7,8 @@

 import {NodePath} from '@babel/core';
 import * as t from '@babel/types';
-import {CompilerError} from '../CompilerError';
-import {ProgramContext} from './Imports';
-import {ExternalFunction} from '..';
+import {PluginOptions} from './Options';

-/**
- * Gating rewrite for function declarations which are referenced before their
- * declaration site.
- *
- * ```js
- * // original
- * export default React.memo(Foo);
- * function Foo() { ... }
- *
- * // React compiler optimized + gated
- * import {gating} from 'myGating';
- * export default React.memo(Foo);
- * const gating_result = gating();  <- inserted
- * function Foo_optimized() {}      <- inserted
- * function Foo_unoptimized() {}    <- renamed from Foo
- * function Foo() {                 <- inserted function, which can be hoisted by JS engines
- *   if (gating_result) return Foo_optimized();
- *   else return Foo_unoptimized();
- * }
- * ```
- */
-function insertAdditionalFunctionDeclaration(
-  fnPath: NodePath<t.FunctionDeclaration>,
-  compiled: t.FunctionDeclaration,
-  programContext: ProgramContext,
-  gatingFunctionIdentifierName: string,
-): void {
-  const originalFnName = fnPath.node.id;
-  const originalFnParams = fnPath.node.params;
-  const compiledParams = fnPath.node.params;
-  /**
-   * Note that other than `export default function() {}`, all other function
-   * declarations must have a binding identifier. Since default exports cannot
-   * be referenced, it's safe to assume that all function declarations passed
-   * here will have an identifier.
-   * https://tc39.es/ecma262/multipage/ecmascript-language-functions-and-classes.html#sec-function-definitions
-   */
-  CompilerError.invariant(originalFnName != null && compiled.id != null, {
-    reason:
-      'Expected function declarations that are referenced elsewhere to have a named identifier',
-    description: null,
-    details: [
-      {
-        kind: 'error',
-        loc: fnPath.node.loc ?? null,
-        message: null,
-      },
-    ],
-  });
-  CompilerError.invariant(originalFnParams.length === compiledParams.length, {
-    reason:
-      'Expected React Compiler optimized function declarations to have the same number of parameters as source',
-    description: null,
-    details: [
-      {
-        kind: 'error',
-        loc: fnPath.node.loc ?? null,
-        message: null,
-      },
-    ],
-  });
-
-  const gatingCondition = t.identifier(
-    programContext.newUid(`${gatingFunctionIdentifierName}_result`),
-  );
-  const unoptimizedFnName = t.identifier(
-    programContext.newUid(`${originalFnName.name}_unoptimized`),
-  );
-  const optimizedFnName = t.identifier(
-    programContext.newUid(`${originalFnName.name}_optimized`),
-  );
-  /**
-   * Step 1: rename existing functions
-   */
-  compiled.id.name = optimizedFnName.name;
-  fnPath.get('id').replaceInline(unoptimizedFnName);
-
-  /**
-   * Step 2: insert new function declaration
-   */
-  const newParams: Array<t.Identifier | t.RestElement> = [];
-  const genNewArgs: Array<() => t.Identifier | t.SpreadElement> = [];
-  for (let i = 0; i < originalFnParams.length; i++) {
-    const argName = `arg${i}`;
-    if (originalFnParams[i].type === 'RestElement') {
-      newParams.push(t.restElement(t.identifier(argName)));
-      genNewArgs.push(() => t.spreadElement(t.identifier(argName)));
-    } else {
-      newParams.push(t.identifier(argName));
-      genNewArgs.push(() => t.identifier(argName));
-    }
-  }
-  // insertAfter called in reverse order of how nodes should appear in program
-  fnPath.insertAfter(
-    t.functionDeclaration(
-      originalFnName,
-      newParams,
-      t.blockStatement([
-        t.ifStatement(
-          gatingCondition,
-          t.returnStatement(
-            t.callExpression(
-              compiled.id,
-              genNewArgs.map(fn => fn()),
-            ),
-          ),
-          t.returnStatement(
-            t.callExpression(
-              unoptimizedFnName,
-              genNewArgs.map(fn => fn()),
-            ),
-          ),
-        ),
-      ]),
-    ),
-  );
-  fnPath.insertBefore(
-    t.variableDeclaration('const', [
-      t.variableDeclarator(
-        gatingCondition,
-        t.callExpression(t.identifier(gatingFunctionIdentifierName), []),
-      ),
-    ]),
-  );
-  fnPath.insertBefore(compiled);
-}
 export function insertGatedFunctionDeclaration(
  fnPath: NodePath<
    t.FunctionDeclaration | t.ArrowFunctionExpression | t.FunctionExpression
@@ -145,71 +17,48 @@ export function insertGatedFunctionDeclaration(
    | t.FunctionDeclaration
    | t.ArrowFunctionExpression
    | t.FunctionExpression,
-  programContext: ProgramContext,
-  gating: ExternalFunction,
-  referencedBeforeDeclaration: boolean,
+  gating: NonNullable<PluginOptions['gating']>,
 ): void {
-  const gatingImportedName = programContext.addImportSpecifier(gating).name;
-  if (referencedBeforeDeclaration && fnPath.isFunctionDeclaration()) {
-    CompilerError.invariant(compiled.type === 'FunctionDeclaration', {
-      reason: 'Expected compiled node type to match input type',
-      description: `Got ${compiled.type} but expected FunctionDeclaration`,
-      details: [
-        {
-          kind: 'error',
-          loc: fnPath.node.loc ?? null,
-          message: null,
-        },
-      ],
-    });
-    insertAdditionalFunctionDeclaration(
-      fnPath,
-      compiled,
-      programContext,
-      gatingImportedName,
+  const gatingExpression = t.conditionalExpression(
+    t.callExpression(t.identifier(gating.importSpecifierName), []),
+    buildFunctionExpression(compiled),
+    buildFunctionExpression(fnPath.node),
+  );
+
+  /*
+   * Convert function declarations to named variables *unless* this is an
+   * `export default function ...` since `export default const ...` is
+   * not supported. For that case we fall through to replacing w the raw
+   * conditional expression
+   */
+  if (
+    fnPath.parentPath.node.type !== 'ExportDefaultDeclaration' &&
+    fnPath.node.type === 'FunctionDeclaration' &&
+    fnPath.node.id != null
+  ) {
+    fnPath.replaceWith(
+      t.variableDeclaration('const', [
+        t.variableDeclarator(fnPath.node.id, gatingExpression),
+      ]),
+    );
+  } else if (
+    fnPath.parentPath.node.type === 'ExportDefaultDeclaration' &&
+    fnPath.node.type !== 'ArrowFunctionExpression' &&
+    fnPath.node.id != null
+  ) {
+    fnPath.insertAfter(
+      t.exportDefaultDeclaration(t.identifier(fnPath.node.id.name)),
+    );
+    fnPath.parentPath.replaceWith(
+      t.variableDeclaration('const', [
+        t.variableDeclarator(
+          t.identifier(fnPath.node.id.name),
+          gatingExpression,
+        ),
+      ]),
    );
  } else {
-    const gatingExpression = t.conditionalExpression(
-      t.callExpression(t.identifier(gatingImportedName), []),
-      buildFunctionExpression(compiled),
-      buildFunctionExpression(fnPath.node),
-    );
-
-    /*
-     * Convert function declarations to named variables *unless* this is an
-     * `export default function ...` since `export default const ...` is
-     * not supported. For that case we fall through to replacing w the raw
-     * conditional expression
-     */
-    if (
-      fnPath.parentPath.node.type !== 'ExportDefaultDeclaration' &&
-      fnPath.node.type === 'FunctionDeclaration' &&
-      fnPath.node.id != null
-    ) {
-      fnPath.replaceWith(
-        t.variableDeclaration('const', [
-          t.variableDeclarator(fnPath.node.id, gatingExpression),
-        ]),
-      );
-    } else if (
-      fnPath.parentPath.node.type === 'ExportDefaultDeclaration' &&
-      fnPath.node.type !== 'ArrowFunctionExpression' &&
-      fnPath.node.id != null
-    ) {
-      fnPath.insertAfter(
-        t.exportDefaultDeclaration(t.identifier(fnPath.node.id.name)),
-      );
-      fnPath.parentPath.replaceWith(
-        t.variableDeclaration('const', [
-          t.variableDeclarator(
-            t.identifier(fnPath.node.id.name),
-            gatingExpression,
-          ),
-        ]),
-      );
-    } else {
-      fnPath.replaceWith(gatingExpression);
-    }
+    fnPath.replaceWith(gatingExpression);
  }
 }

--- a/compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Imports.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Imports.ts
@@ -7,20 +7,9 @@

 import {NodePath} from '@babel/core';
 import * as t from '@babel/types';
-import {Scope as BabelScope} from '@babel/traverse';
-
-import {CompilerError, ErrorCategory} from '../CompilerError';
-import {
-  EnvironmentConfig,
-  GeneratedSource,
-  NonLocalImportSpecifier,
-} from '../HIR';
-import {getOrInsertWith} from '../Utils/utils';
-import {ExternalFunction, isHookName} from '../HIR/Environment';
-import {Err, Ok, Result} from '../Utils/Result';
-import {LoggerEvent, ParsedPluginOptions} from './Options';
-import {BabelFn, getReactCompilerRuntimeModule} from './Program';
-import {SuppressionRange} from './Suppression';
+import {CompilerError, ErrorSeverity} from '../CompilerError';
+import {EnvironmentConfig, ExternalFunction, GeneratedSource} from '../HIR';
+import {getOrInsertDefault} from '../Utils/utils';

 export function validateRestrictedImports(
  path: NodePath<t.Program>,
@@ -38,7 +27,7 @@ export function validateRestrictedImports(
    ImportDeclaration(importDeclPath) {
      if (restrictedImports.has(importDeclPath.node.source.value)) {
        error.push({
-          category: ErrorCategory.Todo,
+          severity: ErrorSeverity.Todo,
          reason: 'Bailing out due to blocklisted import',
          description: `Import from module ${importDeclPath.node.source.value}`,
          loc: importDeclPath.node.loc ?? null,
@@ -46,267 +35,57 @@ export function validateRestrictedImports(
      }
    },
  });
-  if (error.hasAnyErrors()) {
+  if (error.hasErrors()) {
    return error;
  } else {
    return null;
  }
 }

-type ProgramContextOptions = {
-  program: NodePath<t.Program>;
-  suppressions: Array<SuppressionRange>;
-  opts: ParsedPluginOptions;
-  filename: string | null;
-  code: string | null;
-  hasModuleScopeOptOut: boolean;
-};
-export class ProgramContext {
-  /**
-   * Program and environment context
-   */
-  scope: BabelScope;
-  opts: ParsedPluginOptions;
-  filename: string | null;
-  code: string | null;
-  reactRuntimeModule: string;
-  suppressions: Array<SuppressionRange>;
-  hasModuleScopeOptOut: boolean;
-
-  /*
-   * This is a hack to work around what seems to be a Babel bug. Babel doesn't
-   * consistently respect the `skip()` function to avoid revisiting a node within
-   * a pass, so we use this set to track nodes that we have compiled.
-   */
-  alreadyCompiled: WeakSet<object> | Set<object> = new (WeakSet ?? Set)();
-  // known generated or referenced identifiers in the program
-  knownReferencedNames: Set<string> = new Set();
-  // generated imports
-  imports: Map<string, Map<string, NonLocalImportSpecifier>> = new Map();
-
-  /**
-   * Metadata from compilation
-   */
-  retryErrors: Array<{fn: BabelFn; error: CompilerError}> = [];
-  inferredEffectLocations: Set<t.SourceLocation> = new Set();
-
-  constructor({
-    program,
-    suppressions,
-    opts,
-    filename,
-    code,
-    hasModuleScopeOptOut,
-  }: ProgramContextOptions) {
-    this.scope = program.scope;
-    this.opts = opts;
-    this.filename = filename;
-    this.code = code;
-    this.reactRuntimeModule = getReactCompilerRuntimeModule(opts.target);
-    this.suppressions = suppressions;
-    this.hasModuleScopeOptOut = hasModuleScopeOptOut;
-  }
-
-  isHookName(name: string): boolean {
-    if (this.opts.environment.hookPattern == null) {
-      return isHookName(name);
-    } else {
-      const match = new RegExp(this.opts.environment.hookPattern).exec(name);
-      return (
-        match != null && typeof match[1] === 'string' && isHookName(match[1])
-      );
-    }
-  }
-
-  hasReference(name: string): boolean {
-    return (
-      this.knownReferencedNames.has(name) ||
-      this.scope.hasBinding(name) ||
-      this.scope.hasGlobal(name) ||
-      this.scope.hasReference(name)
-    );
-  }
-
-  newUid(name: string): string {
-    /**
-     * Don't call babel's generateUid for known hook imports, as
-     * InferTypes might eventually type `HookKind` based on callee naming
-     * convention and `_useFoo` is not named as a hook.
-     *
-     * Local uid generation is susceptible to check-before-use bugs since we're
-     * checking for naming conflicts / references long before we actually insert
-     * the import. (see similar logic in HIRBuilder:resolveBinding)
-     */
-    let uid;
-    if (this.isHookName(name)) {
-      uid = name;
-      let i = 0;
-      while (this.hasReference(uid)) {
-        this.knownReferencedNames.add(uid);
-        uid = `${name}_${i++}`;
-      }
-    } else if (!this.hasReference(name)) {
-      uid = name;
-    } else {
-      uid = this.scope.generateUid(name);
-    }
-    this.knownReferencedNames.add(uid);
-    return uid;
-  }
-
-  addMemoCacheImport(): NonLocalImportSpecifier {
-    return this.addImportSpecifier(
-      {
-        source: this.reactRuntimeModule,
-        importSpecifierName: 'c',
-      },
-      '_c',
-    );
-  }
-
-  /**
-   *
-   * @param externalFunction
-   * @param nameHint if defined, will be used as the name of the import specifier
-   * @returns
-   */
-  addImportSpecifier(
-    {source: module, importSpecifierName: specifier}: ExternalFunction,
-    nameHint?: string,
-  ): NonLocalImportSpecifier {
-    const maybeBinding = this.imports.get(module)?.get(specifier);
-    if (maybeBinding != null) {
-      return {...maybeBinding};
-    }
-
-    const binding: NonLocalImportSpecifier = {
-      kind: 'ImportSpecifier',
-      name: this.newUid(nameHint ?? specifier),
-      module,
-      imported: specifier,
-    };
-    getOrInsertWith(this.imports, module, () => new Map()).set(specifier, {
-      ...binding,
-    });
-    return binding;
-  }
-
-  addNewReference(name: string): void {
-    this.knownReferencedNames.add(name);
-  }
-
-  assertGlobalBinding(
-    name: string,
-    localScope?: BabelScope,
-  ): Result<void, CompilerError> {
-    const scope = localScope ?? this.scope;
-    if (!scope.hasReference(name) && !scope.hasBinding(name)) {
-      return Ok(undefined);
-    }
-    const error = new CompilerError();
-    error.push({
-      category: ErrorCategory.Todo,
-      reason: 'Encountered conflicting global in generated program',
-      description: `Conflict from local binding ${name}`,
-      loc: scope.getBinding(name)?.path.node.loc ?? null,
-      suggestions: null,
-    });
-    return Err(error);
-  }
-
-  logEvent(event: LoggerEvent): void {
-    if (this.opts.logger != null) {
-      this.opts.logger.logEvent(this.filename, event);
-    }
-  }
-}
-
-function getExistingImports(
-  program: NodePath<t.Program>,
-): Map<string, NodePath<t.ImportDeclaration>> {
-  const existingImports = new Map<string, NodePath<t.ImportDeclaration>>();
-  program.traverse({
-    ImportDeclaration(path) {
-      if (isNonNamespacedImport(path)) {
-        existingImports.set(path.node.source.value, path);
-      }
-    },
-  });
-  return existingImports;
-}
-
 export function addImportsToProgram(
  path: NodePath<t.Program>,
-  programContext: ProgramContext,
+  importList: Array<ExternalFunction>,
 ): void {
-  const existingImports = getExistingImports(path);
+  const identifiers: Set<string> = new Set();
+  const sortedImports: Map<string, Array<string>> = new Map();
+  for (const {importSpecifierName, source} of importList) {
+    /*
+     * Codegen currently does not rename import specifiers, so we do additional
+     * validation here
+     */
+    CompilerError.invariant(identifiers.has(importSpecifierName) === false, {
+      reason: `Encountered conflicting import specifier for ${importSpecifierName} in Forget config.`,
+      description: null,
+      loc: GeneratedSource,
+      suggestions: null,
+    });
+    CompilerError.invariant(
+      path.scope.hasBinding(importSpecifierName) === false,
+      {
+        reason: `Encountered conflicting import specifiers for ${importSpecifierName} in generated program.`,
+        description: null,
+        loc: GeneratedSource,
+        suggestions: null,
+      },
+    );
+    identifiers.add(importSpecifierName);
+
+    const importSpecifierNameList = getOrInsertDefault(
+      sortedImports,
+      source,
+      [],
+    );
+    importSpecifierNameList.push(importSpecifierName);
+  }
+
  const stmts: Array<t.ImportDeclaration> = [];
-  const sortedModules = [...programContext.imports.entries()].sort(([a], [b]) =>
-    a.localeCompare(b),
-  );
-  for (const [moduleName, importsMap] of sortedModules) {
-    for (const [specifierName, loweredImport] of importsMap) {
-      /**
-       * Assert that the import identifier hasn't already be declared in the program.
-       * Note: we use getBinding here since `Scope.hasBinding` pessimistically returns true
-       * for all allocated uids (from `Scope.getUid`)
-       */
-      CompilerError.invariant(
-        path.scope.getBinding(loweredImport.name) == null,
-        {
-          reason:
-            'Encountered conflicting import specifiers in generated program',
-          description: `Conflict from import ${loweredImport.module}:(${loweredImport.imported} as ${loweredImport.name})`,
-          details: [
-            {
-              kind: 'error',
-              loc: GeneratedSource,
-              message: null,
-            },
-          ],
-          suggestions: null,
-        },
-      );
-      CompilerError.invariant(
-        loweredImport.module === moduleName &&
-          loweredImport.imported === specifierName,
-        {
-          reason:
-            'Found inconsistent import specifier. This is an internal bug.',
-          description: `Expected import ${moduleName}:${specifierName} but found ${loweredImport.module}:${loweredImport.imported}`,
-          details: [
-            {
-              kind: 'error',
-              loc: GeneratedSource,
-              message: null,
-            },
-          ],
-        },
-      );
-    }
-    const sortedImport: Array<NonLocalImportSpecifier> = [
-      ...importsMap.values(),
-    ].sort(({imported: a}, {imported: b}) => a.localeCompare(b));
-    const importSpecifiers = sortedImport.map(specifier => {
-      return t.importSpecifier(
-        t.identifier(specifier.name),
-        t.identifier(specifier.imported),
-      );
+  for (const [source, importSpecifierNameList] of sortedImports) {
+    const importSpecifiers = importSpecifierNameList.map(name => {
+      const id = t.identifier(name);
+      return t.importSpecifier(id, id);
    });

-    /**
-     * If an existing import of this module exists (ie `import { ... } from
-     * '<moduleName>'`), inject new imported specifiers into the list of
-     * destructured variables.
-     */
-    const maybeExistingImports = existingImports.get(moduleName);
-    if (maybeExistingImports != null) {
-      maybeExistingImports.pushContainer('specifiers', importSpecifiers);
-    } else {
-      stmts.push(
-        t.importDeclaration(importSpecifiers, t.stringLiteral(moduleName)),
-      );
-    }
+    stmts.push(t.importDeclaration(importSpecifiers, t.stringLiteral(source)));
  }
  path.unshiftContainer('body', stmts);
 }
@@ -314,12 +93,13 @@ export function addImportsToProgram(
 /*
 * Matches `import { ... } from <moduleName>;`
 * but not `import * as React from <moduleName>;`
- *         `import type { Foo } from <moduleName>;`
 */
 function isNonNamespacedImport(
  importDeclPath: NodePath<t.ImportDeclaration>,
+  moduleName: string,
 ): boolean {
  return (
+    importDeclPath.get('source').node.value === moduleName &&
    importDeclPath
      .get('specifiers')
      .every(specifier => specifier.isImportSpecifier()) &&
@@ -327,3 +107,94 @@ function isNonNamespacedImport(
    importDeclPath.node.importKind !== 'typeof'
  );
 }
+
+function hasExistingNonNamespacedImportOfModule(
+  program: NodePath<t.Program>,
+  moduleName: string,
+): boolean {
+  let hasExistingImport = false;
+  program.traverse({
+    ImportDeclaration(importDeclPath) {
+      if (isNonNamespacedImport(importDeclPath, moduleName)) {
+        hasExistingImport = true;
+      }
+    },
+  });
+
+  return hasExistingImport;
+}
+
+/*
+ * If an existing import of React exists (ie `import { ... } from '<moduleName>'`), inject useMemoCache
+ * into the list of destructured variables.
+ */
+function addMemoCacheFunctionSpecifierToExistingImport(
+  program: NodePath<t.Program>,
+  moduleName: string,
+  identifierName: string,
+): boolean {
+  let didInsertUseMemoCache = false;
+  program.traverse({
+    ImportDeclaration(importDeclPath) {
+      if (
+        !didInsertUseMemoCache &&
+        isNonNamespacedImport(importDeclPath, moduleName)
+      ) {
+        importDeclPath.pushContainer(
+          'specifiers',
+          t.importSpecifier(t.identifier(identifierName), t.identifier('c')),
+        );
+        didInsertUseMemoCache = true;
+      }
+    },
+  });
+  return didInsertUseMemoCache;
+}
+
+export function updateMemoCacheFunctionImport(
+  program: NodePath<t.Program>,
+  moduleName: string,
+  useMemoCacheIdentifier: string,
+): void {
+  /*
+   * If there isn't already an import of * as React, insert it so useMemoCache doesn't
+   * throw
+   */
+  const hasExistingImport = hasExistingNonNamespacedImportOfModule(
+    program,
+    moduleName,
+  );
+
+  if (hasExistingImport) {
+    const didUpdateImport = addMemoCacheFunctionSpecifierToExistingImport(
+      program,
+      moduleName,
+      useMemoCacheIdentifier,
+    );
+    if (!didUpdateImport) {
+      throw new Error(
+        `Expected an ImportDeclaration of \`${moduleName}\` in order to update ImportSpecifiers with useMemoCache`,
+      );
+    }
+  } else {
+    addMemoCacheFunctionImportDeclaration(
+      program,
+      moduleName,
+      useMemoCacheIdentifier,
+    );
+  }
+}
+
+function addMemoCacheFunctionImportDeclaration(
+  program: NodePath<t.Program>,
+  moduleName: string,
+  localName: string,
+): void {
+  program.unshiftContainer(
+    'body',
+    t.importDeclaration(
+      [t.importSpecifier(t.identifier(localName), t.identifier('c'))],
+      t.stringLiteral(moduleName),
+    ),
+  );
+}
--- a/compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Options.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Options.ts
@@ -7,17 +7,11 @@

 import * as t from '@babel/types';
 import {z} from 'zod';
-import {
-  CompilerDiagnostic,
-  CompilerError,
-  CompilerErrorDetail,
-  CompilerErrorDetailOptions,
-} from '../CompilerError';
+import {CompilerError, CompilerErrorDetailOptions} from '../CompilerError';
 import {
  EnvironmentConfig,
  ExternalFunction,
  parseEnvironmentConfig,
-  tryParseExternalFunction,
 } from '../HIR/Environment';
 import {hasOwnProperty} from '../Utils/utils';
 import {fromZodError} from 'zod-validation-error';
@@ -42,17 +36,9 @@ const PanicThresholdOptionsSchema = z.enum([
 ]);

 export type PanicThresholdOptions = z.infer<typeof PanicThresholdOptionsSchema>;
-const DynamicGatingOptionsSchema = z.object({
-  source: z.string(),
-});
-export type DynamicGatingOptions = z.infer<typeof DynamicGatingOptionsSchema>;
-const CustomOptOutDirectiveSchema = z
-  .nullable(z.array(z.string()))
-  .default(null);
-type CustomOptOutDirective = z.infer<typeof CustomOptOutDirectiveSchema>;

-export type PluginOptions = Partial<{
-  environment: Partial<EnvironmentConfig>;
+export type PluginOptions = {
+  environment: EnvironmentConfig;

  logger: Logger | null;

@@ -78,28 +64,6 @@ export type PluginOptions = Partial<{
   */
  gating: ExternalFunction | null;

-  /**
-   * If specified, this enables dynamic gating which matches `use memo if(...)`
-   * directives.
-   *
-   * Example usage:
-   * ```js
-   * // @dynamicGating:{"source":"myModule"}
-   * export function MyComponent() {
-   *   'use memo if(isEnabled)';
-   *    return <div>...</div>;
-   * }
-   * ```
-   * This will emit:
-   * ```js
-   * import {isEnabled} from 'myModule';
-   * export const MyComponent = isEnabled()
-   *   ? <optimized version>
-   *   : <original version>;
-   * ```
-   */
-  dynamicGating: DynamicGatingOptions | null;
-
  panicThreshold: PanicThresholdOptions;

  /*
@@ -133,25 +97,15 @@ export type PluginOptions = Partial<{
   * provided rules will skip compilation. To disable this feature (never bailout of compilation
   * even if the default ESLint is suppressed), pass an empty array.
   */
-  eslintSuppressionRules: Array<string> | null | undefined;
+  eslintSuppressionRules?: Array<string> | null | undefined;

-  /**
-   * Whether to report "suppression" errors for Flow suppressions. If false, suppression errors
-   * are only emitted for ESLint suppressions
-   */
  flowSuppressions: boolean;
-
  /*
   * Ignore 'use no forget' annotations. Helpful during testing but should not be used in production.
   */
  ignoreUseNoForget: boolean;

-  /**
-   * Unstable / do not use
-   */
-  customOptOutDirectives: CustomOptOutDirective;
-
-  sources: Array<string> | ((filename: string) => boolean) | null;
+  sources?: Array<string> | ((filename: string) => boolean) | null;

  /**
   * The compiler has customized support for react-native-reanimated, intended as a temporary workaround.
@@ -166,11 +120,7 @@ export type PluginOptions = Partial<{
   * a userspace approximation of runtime APIs.
   */
  target: CompilerReactTarget;
-}>;
-
-export type ParsedPluginOptions = Required<
-  Omit<PluginOptions, 'environment'>
-> & {environment: EnvironmentConfig};
+};

 const CompilerReactTargetSchema = z.union([
  z.literal('17'),
@@ -231,14 +181,12 @@ export type LoggerEvent =
  | CompileDiagnosticEvent
  | CompileSkipEvent
  | PipelineErrorEvent
-  | TimingEvent
-  | AutoDepsDecorationsEvent
-  | AutoDepsEligibleEvent;
+  | TimingEvent;

 export type CompileErrorEvent = {
  kind: 'CompileError';
  fnLoc: t.SourceLocation | null;
-  detail: CompilerErrorDetail | CompilerDiagnostic;
+  detail: CompilerErrorDetailOptions;
 };
 export type CompileDiagnosticEvent = {
  kind: 'CompileDiagnostic';
@@ -270,30 +218,19 @@ export type TimingEvent = {
  kind: 'Timing';
  measurement: PerformanceMeasure;
 };
-export type AutoDepsDecorationsEvent = {
-  kind: 'AutoDepsDecorations';
-  fnLoc: t.SourceLocation;
-  decorations: Array<t.SourceLocation>;
-};
-export type AutoDepsEligibleEvent = {
-  kind: 'AutoDepsEligible';
-  fnLoc: t.SourceLocation;
-  depArrayLoc: t.SourceLocation;
-};

 export type Logger = {
  logEvent: (filename: string | null, event: LoggerEvent) => void;
  debugLogIRs?: (value: CompilerPipelineValue) => void;
 };

-export const defaultOptions: ParsedPluginOptions = {
+export const defaultOptions: PluginOptions = {
  compilationMode: 'infer',
  panicThreshold: 'none',
  environment: parseEnvironmentConfig({}).unwrap(),
  logger: null,
  gating: null,
  noEmit: false,
-  dynamicGating: null,
  eslintSuppressionRules: null,
  flowSuppressions: true,
  ignoreUseNoForget: false,
@@ -301,11 +238,10 @@ export const defaultOptions: ParsedPluginOptions = {
    return filename.indexOf('node_modules') === -1;
  },
  enableReanimatedCheck: true,
-  customOptOutDirectives: null,
  target: '19',
-};
+} as const;

-export function parsePluginOptions(obj: unknown): ParsedPluginOptions {
+export function parsePluginOptions(obj: unknown): PluginOptions {
  if (obj == null || typeof obj !== 'object') {
    return defaultOptions;
  }
@@ -335,48 +271,6 @@ export function parsePluginOptions(obj: unknown): ParsedPluginOptions {
          parsedOptions[key] = parseTargetConfig(value);
          break;
        }
-        case 'gating': {
-          if (value == null) {
-            parsedOptions[key] = null;
-          } else {
-            parsedOptions[key] = tryParseExternalFunction(value);
-          }
-          break;
-        }
-        case 'dynamicGating': {
-          if (value == null) {
-            parsedOptions[key] = null;
-          } else {
-            const result = DynamicGatingOptionsSchema.safeParse(value);
-            if (result.success) {
-              parsedOptions[key] = result.data;
-            } else {
-              CompilerError.throwInvalidConfig({
-                reason:
-                  'Could not parse dynamic gating. Update React Compiler config to fix the error',
-                description: `${fromZodError(result.error)}`,
-                loc: null,
-                suggestions: null,
-              });
-            }
-          }
-          break;
-        }
-        case 'customOptOutDirectives': {
-          const result = CustomOptOutDirectiveSchema.safeParse(value);
-          if (result.success) {
-            parsedOptions[key] = result.data;
-          } else {
-            CompilerError.throwInvalidConfig({
-              reason:
-                'Could not parse custom opt out directives. Update React Compiler config to fix the error',
-              description: `${fromZodError(result.error)}`,
-              loc: null,
-              suggestions: null,
-            });
-          }
-          break;
-        }
        default: {
          parsedOptions[key] = value;
        }
--- a/compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Pipeline.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Pipeline.ts
@@ -8,7 +8,7 @@
 import {NodePath} from '@babel/traverse';
 import * as t from '@babel/types';
 import prettyFormat from 'pretty-format';
-import {Logger, ProgramContext} from '.';
+import {Logger} from '.';
 import {
  HIRFunction,
  ReactiveFunction,
@@ -24,7 +24,6 @@ import {
  pruneUnusedLabelsHIR,
 } from '../HIR';
 import {
-  CompilerMode,
  Environment,
  EnvironmentConfig,
  ReactFunctionType,
@@ -33,7 +32,9 @@ import {findContextIdentifiers} from '../HIR/FindContextIdentifiers';
 import {
  analyseFunctions,
  dropManualMemoization,
+  inferMutableRanges,
  inferReactivePlaces,
+  inferReferenceEffects,
  inlineImmediatelyInvokedFunctionExpressions,
  inferEffectDependencies,
 } from '../Inference';
@@ -90,20 +91,15 @@ import {
 } from '../Validation';
 import {validateLocalsNotReassignedAfterRender} from '../Validation/ValidateLocalsNotReassignedAfterRender';
 import {outlineFunctions} from '../Optimization/OutlineFunctions';
+import {propagatePhiTypes} from '../TypeInference/PropagatePhiTypes';
 import {lowerContextAccess} from '../Optimization/LowerContextAccess';
-import {validateNoSetStateInEffects} from '../Validation/ValidateNoSetStateInEffects';
+import {validateNoSetStateInPassiveEffects} from '../Validation/ValidateNoSetStateInPassiveEffects';
 import {validateNoJSXInTryStatement} from '../Validation/ValidateNoJSXInTryStatement';
 import {propagateScopeDependenciesHIR} from '../HIR/PropagateScopeDependenciesHIR';
 import {outlineJSX} from '../Optimization/OutlineJsx';
 import {optimizePropsMethodCalls} from '../Optimization/OptimizePropsMethodCalls';
 import {transformFire} from '../Transform';
-import {validateNoImpureFunctionsInRender} from '../Validation/ValidateNoImpureFunctionsInRender';
-import {validateStaticComponents} from '../Validation/ValidateStaticComponents';
-import {validateNoFreezingKnownMutableFunctions} from '../Validation/ValidateNoFreezingKnownMutableFunctions';
-import {inferMutationAliasingEffects} from '../Inference/InferMutationAliasingEffects';
-import {inferMutationAliasingRanges} from '../Inference/InferMutationAliasingRanges';
-import {validateNoDerivedComputationsInEffects} from '../Validation/ValidateNoDerivedComputationsInEffects';
-import {nameAnonymousFunctions} from '../Transform/NameAnonymousFunctions';
+import {validateNoImpureFunctionsInRender} from '../Validation/ValiateNoImpureFunctionsInRender';

 export type CompilerPipelineValue =
  | {kind: 'ast'; name: string; value: CodegenFunction}
@@ -117,8 +113,7 @@ function run(
  >,
  config: EnvironmentConfig,
  fnType: ReactFunctionType,
-  mode: CompilerMode,
-  programContext: ProgramContext,
+  useMemoCacheIdentifier: string,
  logger: Logger | null,
  filename: string | null,
  code: string | null,
@@ -127,14 +122,12 @@ function run(
  const env = new Environment(
    func.scope,
    fnType,
-    mode,
    config,
    contextIdentifiers,
-    func,
    logger,
    filename,
    code,
-    programContext,
+    useMemoCacheIdentifier,
  );
  env.logger?.debugLogIRs?.({
    kind: 'debug',
@@ -164,15 +157,15 @@ function runWithEnvironment(
  log({kind: 'hir', name: 'PruneMaybeThrows', value: hir});

  validateContextVariableLValues(hir);
-  validateUseMemo(hir).unwrap();
+  validateUseMemo(hir);

  if (
-    env.isInferredMemoEnabled &&
    !env.config.enablePreserveExistingManualUseMemo &&
    !env.config.disableMemoizationForDebugging &&
-    !env.config.enableChangeDetectionForDebugging
+    !env.config.enableChangeDetectionForDebugging &&
+    !env.config.enableMinimalTransformsForRetry
  ) {
-    dropManualMemoization(hir).unwrap();
+    dropManualMemoization(hir);
    log({kind: 'hir', name: 'DropManualMemoization', value: hir});
  }

@@ -203,13 +196,8 @@ function runWithEnvironment(
  inferTypes(hir);
  log({kind: 'hir', name: 'InferTypes', value: hir});

-  if (env.isInferredMemoEnabled) {
-    if (env.config.validateHooksUsage) {
-      validateHooksUsage(hir).unwrap();
-    }
-    if (env.config.validateNoCapitalizedCalls) {
-      validateNoCapitalizedCalls(hir).unwrap();
-    }
+  if (env.config.validateHooksUsage) {
+    validateHooksUsage(hir);
  }

  if (env.config.enableFire) {
@@ -217,6 +205,10 @@ function runWithEnvironment(
    log({kind: 'hir', name: 'TransformFire', value: hir});
  }

+  if (env.config.validateNoCapitalizedCalls) {
+    validateNoCapitalizedCalls(hir);
+  }
+
  if (env.config.lowerContextAccess) {
    lowerContextAccess(hir, env.config.lowerContextAccess);
  }
@@ -227,13 +219,10 @@ function runWithEnvironment(
  analyseFunctions(hir);
  log({kind: 'hir', name: 'AnalyseFunctions', value: hir});

-  const mutabilityAliasingErrors = inferMutationAliasingEffects(hir);
-  log({kind: 'hir', name: 'InferMutationAliasingEffects', value: hir});
-  if (env.isInferredMemoEnabled) {
-    if (mutabilityAliasingErrors.isErr()) {
-      throw mutabilityAliasingErrors.unwrapErr();
-    }
-  }
+  inferReferenceEffects(hir);
+  log({kind: 'hir', name: 'InferReferenceEffects', value: hir});
+
+  validateLocalsNotReassignedAfterRender(hir);

  // Note: Has to come after infer reference effects because "dead" code may still affect inference
  deadCodeElimination(hir);
@@ -247,47 +236,31 @@ function runWithEnvironment(
  pruneMaybeThrows(hir);
  log({kind: 'hir', name: 'PruneMaybeThrows', value: hir});

-  const mutabilityAliasingRangeErrors = inferMutationAliasingRanges(hir, {
-    isFunctionExpression: false,
-  });
-  log({kind: 'hir', name: 'InferMutationAliasingRanges', value: hir});
-  if (env.isInferredMemoEnabled) {
-    if (mutabilityAliasingRangeErrors.isErr()) {
-      throw mutabilityAliasingRangeErrors.unwrapErr();
-    }
-    validateLocalsNotReassignedAfterRender(hir);
+  inferMutableRanges(hir);
+  log({kind: 'hir', name: 'InferMutableRanges', value: hir});
+
+  if (env.config.assertValidMutableRanges) {
+    assertValidMutableRanges(hir);
  }

-  if (env.isInferredMemoEnabled) {
-    if (env.config.assertValidMutableRanges) {
-      assertValidMutableRanges(hir);
-    }
+  if (env.config.validateRefAccessDuringRender) {
+    validateNoRefAccessInRender(hir);
+  }

-    if (env.config.validateRefAccessDuringRender) {
-      validateNoRefAccessInRender(hir).unwrap();
-    }
+  if (env.config.validateNoSetStateInRender) {
+    validateNoSetStateInRender(hir);
+  }

-    if (env.config.validateNoSetStateInRender) {
-      validateNoSetStateInRender(hir).unwrap();
-    }
+  if (env.config.validateNoSetStateInPassiveEffects) {
+    validateNoSetStateInPassiveEffects(hir);
+  }

-    if (env.config.validateNoDerivedComputationsInEffects) {
-      validateNoDerivedComputationsInEffects(hir);
-    }
+  if (env.config.validateNoJSXInTryStatements) {
+    validateNoJSXInTryStatement(hir);
+  }

-    if (env.config.validateNoSetStateInEffects) {
-      env.logErrors(validateNoSetStateInEffects(hir, env));
-    }
-
-    if (env.config.validateNoJSXInTryStatements) {
-      env.logErrors(validateNoJSXInTryStatement(hir));
-    }
-
-    if (env.config.validateNoImpureFunctionsInRender) {
-      validateNoImpureFunctionsInRender(hir).unwrap();
-    }
-
-    validateNoFreezingKnownMutableFunctions(hir).unwrap();
+  if (env.config.validateNoImpureFunctionsInRender) {
+    validateNoImpureFunctionsInRender(hir);
  }

  inferReactivePlaces(hir);
@@ -300,16 +273,14 @@ function runWithEnvironment(
    value: hir,
  });

-  if (env.isInferredMemoEnabled) {
-    if (env.config.validateStaticComponents) {
-      env.logErrors(validateStaticComponents(hir));
-    }
+  propagatePhiTypes(hir);
+  log({
+    kind: 'hir',
+    name: 'PropagatePhiTypes',
+    value: hir,
+  });

-    /**
-     * Only create reactive scopes (which directly map to generated memo blocks)
-     * if inferred memoization is enabled. This makes all later passes which
-     * transform reactive-scope labeled instructions no-ops.
-     */
+  if (!env.config.enableMinimalTransformsForRetry) {
    inferReactiveScopeVariables(hir);
    log({kind: 'hir', name: 'InferReactiveScopeVariables', value: hir});
  }
@@ -325,15 +296,6 @@ function runWithEnvironment(
    outlineJSX(hir);
  }

-  if (env.config.enableNameAnonymousFunctions) {
-    nameAnonymousFunctions(hir);
-    log({
-      kind: 'hir',
-      name: 'NameAnonymousFunctions',
-      value: hir,
-    });
-  }
-
  if (env.config.enableFunctionOutlining) {
    outlineFunctions(hir, fbtOperands);
    log({kind: 'hir', name: 'OutlineFunctions', value: hir});
@@ -408,11 +370,6 @@ function runWithEnvironment(

  if (env.config.inferEffectDependencies) {
    inferEffectDependencies(hir);
-    log({
-      kind: 'hir',
-      name: 'InferEffectDependencies',
-      value: hir,
-    });
  }

  if (env.config.inlineJsxTransform) {
@@ -535,14 +492,14 @@ function runWithEnvironment(
  });

  if (env.config.validateMemoizedEffectDependencies) {
-    validateMemoizedEffectDependencies(reactiveFunction).unwrap();
+    validateMemoizedEffectDependencies(reactiveFunction);
  }

  if (
    env.config.enablePreserveExistingMemoizationGuarantees ||
    env.config.validatePreserveExistingMemoizationGuarantees
  ) {
-    validatePreservedManualMemoization(reactiveFunction).unwrap();
+    validatePreservedManualMemoization(reactiveFunction);
  }

  const ast = codegenFunction(reactiveFunction, {
@@ -572,8 +529,7 @@ export function compileFn(
  >,
  config: EnvironmentConfig,
  fnType: ReactFunctionType,
-  mode: CompilerMode,
-  programContext: ProgramContext,
+  useMemoCacheIdentifier: string,
  logger: Logger | null,
  filename: string | null,
  code: string | null,
@@ -582,8 +538,7 @@ export function compileFn(
    func,
    config,
    fnType,
-    mode,
-    programContext,
+    useMemoCacheIdentifier,
    logger,
    filename,
    code,
--- a/compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Program.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Program.ts
--- a/compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Reanimated.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Reanimated.ts
@@ -1,13 +1,6 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
 import type * as BabelCore from '@babel/core';
 import {hasOwnProperty} from '../Utils/utils';
-import {ParsedPluginOptions} from './Options';
+import {PluginOptions} from './Options';

 function hasModule(name: string): boolean {
  if (typeof require === 'undefined') {
@@ -52,9 +45,7 @@ export function pipelineUsesReanimatedPlugin(
  return hasModule('react-native-reanimated');
 }

-export function injectReanimatedFlag(
-  options: ParsedPluginOptions,
-): ParsedPluginOptions {
+export function injectReanimatedFlag(options: PluginOptions): PluginOptions {
  return {
    ...options,
    environment: {
--- a/compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Suppression.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Suppression.ts
@@ -8,10 +8,10 @@
 import {NodePath} from '@babel/core';
 import * as t from '@babel/types';
 import {
-  CompilerDiagnostic,
  CompilerError,
+  CompilerErrorDetail,
  CompilerSuggestionOperation,
-  ErrorCategory,
+  ErrorSeverity,
 } from '../CompilerError';
 import {assertExhaustive} from '../Utils/utils';
 import {GeneratedSource} from '../HIR';
@@ -86,18 +86,12 @@ export function findProgramSuppressions(
  let enableComment: t.Comment | null = null;
  let source: SuppressionSource | null = null;

-  let disableNextLinePattern: RegExp | null = null;
-  let disablePattern: RegExp | null = null;
-  let enablePattern: RegExp | null = null;
-  if (ruleNames.length !== 0) {
-    const rulePattern = `(${ruleNames.join('|')})`;
-    disableNextLinePattern = new RegExp(
-      `eslint-disable-next-line ${rulePattern}`,
-    );
-    disablePattern = new RegExp(`eslint-disable ${rulePattern}`);
-    enablePattern = new RegExp(`eslint-enable ${rulePattern}`);
-  }
-
+  const rulePattern = `(${ruleNames.join('|')})`;
+  const disableNextLinePattern = new RegExp(
+    `eslint-disable-next-line ${rulePattern}`,
+  );
+  const disablePattern = new RegExp(`eslint-disable ${rulePattern}`);
+  const enablePattern = new RegExp(`eslint-enable ${rulePattern}`);
  const flowSuppressionPattern = new RegExp(
    '\\$(FlowFixMe\\w*|FlowExpectedError|FlowIssue)\\[react\\-rule',
  );
@@ -113,7 +107,6 @@ export function findProgramSuppressions(
       * CommentLine within the block.
       */
      disableComment == null &&
-      disableNextLinePattern != null &&
      disableNextLinePattern.test(comment.value)
    ) {
      disableComment = comment;
@@ -131,16 +124,12 @@ export function findProgramSuppressions(
      source = 'Flow';
    }

-    if (disablePattern != null && disablePattern.test(comment.value)) {
+    if (disablePattern.test(comment.value)) {
      disableComment = comment;
      source = 'Eslint';
    }

-    if (
-      enablePattern != null &&
-      enablePattern.test(comment.value) &&
-      source === 'Eslint'
-    ) {
+    if (enablePattern.test(comment.value) && source === 'Eslint') {
      enableComment = comment;
    }

@@ -163,14 +152,7 @@ export function suppressionsToCompilerError(
 ): CompilerError {
  CompilerError.invariant(suppressionRanges.length !== 0, {
    reason: `Expected at least suppression comment source range`,
-    description: null,
-    details: [
-      {
-        kind: 'error',
-        loc: GeneratedSource,
-        message: null,
-      },
-    ],
+    loc: GeneratedSource,
  });
  const error = new CompilerError();
  for (const suppressionRange of suppressionRanges) {
@@ -199,11 +181,12 @@ export function suppressionsToCompilerError(
          'Unhandled suppression source',
        );
    }
-    error.pushDiagnostic(
-      CompilerDiagnostic.create({
-        reason: reason,
-        description: `React Compiler only works when your components follow all the rules of React, disabling them may result in unexpected or incorrect behavior. Found suppression \`${suppressionRange.disableComment.value.trim()}\``,
-        category: ErrorCategory.Suppression,
+    error.pushErrorDetail(
+      new CompilerErrorDetail({
+        reason: `${reason}. React Compiler only works when your components follow all the rules of React, disabling them may result in unexpected or incorrect behavior`,
+        description: suppressionRange.disableComment.value.trim(),
+        severity: ErrorSeverity.InvalidReact,
+        loc: suppressionRange.disableComment.loc ?? null,
        suggestions: [
          {
            description: suggestion,
@@ -214,10 +197,6 @@ export function suppressionsToCompilerError(
            op: CompilerSuggestionOperation.Remove,
          },
        ],
-      }).withDetails({
-        kind: 'error',
-        loc: suppressionRange.disableComment.loc ?? null,
-        message: 'Found React rule suppression',
      }),
    );
  }
--- a/compiler/packages/babel-plugin-react-compiler/src/Entrypoint/ValidateNoUntransformedReferences.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/Entrypoint/ValidateNoUntransformedReferences.ts
@@ -1,341 +0,0 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
-import {NodePath} from '@babel/core';
-import * as t from '@babel/types';
-
-import {CompilerError, EnvironmentConfig, Logger} from '..';
-import {getOrInsertWith} from '../Utils/utils';
-import {Environment, GeneratedSource} from '../HIR';
-import {DEFAULT_EXPORT} from '../HIR/Environment';
-import {CompileProgramMetadata} from './Program';
-import {
-  CompilerDiagnostic,
-  CompilerDiagnosticOptions,
-  ErrorCategory,
-} from '../CompilerError';
-
-function throwInvalidReact(
-  options: CompilerDiagnosticOptions,
-  {logger, filename}: TraversalState,
-): never {
-  logger?.logEvent(filename, {
-    kind: 'CompileError',
-    fnLoc: null,
-    detail: new CompilerDiagnostic(options),
-  });
-  CompilerError.throwDiagnostic(options);
-}
-
-function isAutodepsSigil(
-  arg: NodePath<t.ArgumentPlaceholder | t.SpreadElement | t.Expression>,
-): boolean {
-  // Check for AUTODEPS identifier imported from React
-  if (arg.isIdentifier() && arg.node.name === 'AUTODEPS') {
-    const binding = arg.scope.getBinding(arg.node.name);
-    if (binding && binding.path.isImportSpecifier()) {
-      const importSpecifier = binding.path.node as t.ImportSpecifier;
-      if (importSpecifier.imported.type === 'Identifier') {
-        return (importSpecifier.imported as t.Identifier).name === 'AUTODEPS';
-      }
-    }
-    return false;
-  }
-
-  // Check for React.AUTODEPS member expression
-  if (arg.isMemberExpression() && !arg.node.computed) {
-    const object = arg.get('object');
-    const property = arg.get('property');
-
-    if (
-      object.isIdentifier() &&
-      object.node.name === 'React' &&
-      property.isIdentifier() &&
-      property.node.name === 'AUTODEPS'
-    ) {
-      return true;
-    }
-  }
-
-  return false;
-}
-function assertValidEffectImportReference(
-  autodepsIndex: number,
-  paths: Array<NodePath<t.Node>>,
-  context: TraversalState,
-): void {
-  for (const path of paths) {
-    const parent = path.parentPath;
-    if (parent != null && parent.isCallExpression()) {
-      const args = parent.get('arguments');
-      const maybeCalleeLoc = path.node.loc;
-      const hasInferredEffect =
-        maybeCalleeLoc != null &&
-        context.inferredEffectLocations.has(maybeCalleeLoc);
-      /**
-       * Error on effect calls that still have AUTODEPS in their args
-       */
-      const hasAutodepsArg = args.some(isAutodepsSigil);
-      if (hasAutodepsArg && !hasInferredEffect) {
-        const maybeErrorDiagnostic = matchCompilerDiagnostic(
-          path,
-          context.transformErrors,
-        );
-        /**
-         * Note that we cannot easily check the type of the first argument here,
-         * as it may have already been transformed by the compiler (and not
-         * memoized).
-         */
-        throwInvalidReact(
-          {
-            category: ErrorCategory.AutomaticEffectDependencies,
-            reason:
-              'Cannot infer dependencies of this effect. This will break your build!',
-            description:
-              'To resolve, either pass a dependency array or fix reported compiler bailout diagnostics' +
-              (maybeErrorDiagnostic ? ` ${maybeErrorDiagnostic}` : ''),
-            details: [
-              {
-                kind: 'error',
-                message: 'Cannot infer dependencies',
-                loc: parent.node.loc ?? GeneratedSource,
-              },
-            ],
-          },
-          context,
-        );
-      }
-    }
-  }
-}
-
-function assertValidFireImportReference(
-  paths: Array<NodePath<t.Node>>,
-  context: TraversalState,
-): void {
-  if (paths.length > 0) {
-    const maybeErrorDiagnostic = matchCompilerDiagnostic(
-      paths[0],
-      context.transformErrors,
-    );
-    throwInvalidReact(
-      {
-        category: ErrorCategory.Fire,
-        reason: '[Fire] Untransformed reference to compiler-required feature.',
-        description:
-          'Either remove this `fire` call or ensure it is successfully transformed by the compiler' +
-          (maybeErrorDiagnostic != null ? ` ${maybeErrorDiagnostic}` : ''),
-        details: [
-          {
-            kind: 'error',
-            message: 'Untransformed `fire` call',
-            loc: paths[0].node.loc ?? GeneratedSource,
-          },
-        ],
-      },
-      context,
-    );
-  }
-}
-export default function validateNoUntransformedReferences(
-  path: NodePath<t.Program>,
-  filename: string | null,
-  logger: Logger | null,
-  env: EnvironmentConfig,
-  compileResult: CompileProgramMetadata | null,
-): void {
-  const moduleLoadChecks = new Map<
-    string,
-    Map<string, CheckInvalidReferenceFn>
-  >();
-  if (env.enableFire) {
-    /**
-     * Error on any untransformed references to `fire` (e.g. including non-call
-     * expressions)
-     */
-    for (const module of Environment.knownReactModules) {
-      const react = getOrInsertWith(moduleLoadChecks, module, () => new Map());
-      react.set('fire', assertValidFireImportReference);
-    }
-  }
-  if (env.inferEffectDependencies) {
-    for (const {
-      function: {source, importSpecifierName},
-      autodepsIndex,
-    } of env.inferEffectDependencies) {
-      const module = getOrInsertWith(moduleLoadChecks, source, () => new Map());
-      module.set(
-        importSpecifierName,
-        assertValidEffectImportReference.bind(null, autodepsIndex),
-      );
-    }
-  }
-  if (moduleLoadChecks.size > 0) {
-    transformProgram(path, moduleLoadChecks, filename, logger, compileResult);
-  }
-}
-
-type TraversalState = {
-  shouldInvalidateScopes: boolean;
-  program: NodePath<t.Program>;
-  logger: Logger | null;
-  filename: string | null;
-  transformErrors: Array<{fn: NodePath<t.Node>; error: CompilerError}>;
-  inferredEffectLocations: Set<t.SourceLocation>;
-};
-type CheckInvalidReferenceFn = (
-  paths: Array<NodePath<t.Node>>,
-  context: TraversalState,
-) => void;
-
-function validateImportSpecifier(
-  specifier: NodePath<t.ImportSpecifier>,
-  importSpecifierChecks: Map<string, CheckInvalidReferenceFn>,
-  state: TraversalState,
-): void {
-  const imported = specifier.get('imported');
-  const specifierName: string =
-    imported.node.type === 'Identifier'
-      ? imported.node.name
-      : imported.node.value;
-  const checkFn = importSpecifierChecks.get(specifierName);
-  if (checkFn == null) {
-    return;
-  }
-  if (state.shouldInvalidateScopes) {
-    state.shouldInvalidateScopes = false;
-    state.program.scope.crawl();
-  }
-
-  const local = specifier.get('local');
-  const binding = local.scope.getBinding(local.node.name);
-  CompilerError.invariant(binding != null, {
-    reason: 'Expected binding to be found for import specifier',
-    description: null,
-    details: [
-      {
-        kind: 'error',
-        loc: local.node.loc ?? null,
-        message: null,
-      },
-    ],
-  });
-  checkFn(binding.referencePaths, state);
-}
-
-function validateNamespacedImport(
-  specifier: NodePath<t.ImportNamespaceSpecifier | t.ImportDefaultSpecifier>,
-  importSpecifierChecks: Map<string, CheckInvalidReferenceFn>,
-  state: TraversalState,
-): void {
-  if (state.shouldInvalidateScopes) {
-    state.shouldInvalidateScopes = false;
-    state.program.scope.crawl();
-  }
-  const local = specifier.get('local');
-  const binding = local.scope.getBinding(local.node.name);
-  const defaultCheckFn = importSpecifierChecks.get(DEFAULT_EXPORT);
-
-  CompilerError.invariant(binding != null, {
-    reason: 'Expected binding to be found for import specifier',
-    description: null,
-    details: [
-      {
-        kind: 'error',
-        loc: local.node.loc ?? null,
-        message: null,
-      },
-    ],
-  });
-  const filteredReferences = new Map<
-    CheckInvalidReferenceFn,
-    Array<NodePath<t.Node>>
-  >();
-  for (const reference of binding.referencePaths) {
-    if (defaultCheckFn != null) {
-      getOrInsertWith(filteredReferences, defaultCheckFn, () => []).push(
-        reference,
-      );
-    }
-    const parent = reference.parentPath;
-    if (
-      parent != null &&
-      parent.isMemberExpression() &&
-      parent.get('object') === reference
-    ) {
-      if (parent.node.computed || parent.node.property.type !== 'Identifier') {
-        continue;
-      }
-      const checkFn = importSpecifierChecks.get(parent.node.property.name);
-      if (checkFn != null) {
-        getOrInsertWith(filteredReferences, checkFn, () => []).push(parent);
-      }
-    }
-  }
-
-  for (const [checkFn, references] of filteredReferences) {
-    checkFn(references, state);
-  }
-}
-function transformProgram(
-  path: NodePath<t.Program>,
-
-  moduleLoadChecks: Map<string, Map<string, CheckInvalidReferenceFn>>,
-  filename: string | null,
-  logger: Logger | null,
-  compileResult: CompileProgramMetadata | null,
-): void {
-  const traversalState: TraversalState = {
-    shouldInvalidateScopes: true,
-    program: path,
-    filename,
-    logger,
-    transformErrors: compileResult?.retryErrors ?? [],
-    inferredEffectLocations:
-      compileResult?.inferredEffectLocations ?? new Set(),
-  };
-  path.traverse({
-    ImportDeclaration(path: NodePath<t.ImportDeclaration>) {
-      const importSpecifierChecks = moduleLoadChecks.get(
-        path.node.source.value,
-      );
-      if (importSpecifierChecks == null) {
-        return;
-      }
-      const specifiers = path.get('specifiers');
-      for (const specifier of specifiers) {
-        if (specifier.isImportSpecifier()) {
-          validateImportSpecifier(
-            specifier,
-            importSpecifierChecks,
-            traversalState,
-          );
-        } else {
-          validateNamespacedImport(
-            specifier as NodePath<
-              t.ImportNamespaceSpecifier | t.ImportDefaultSpecifier
-            >,
-            importSpecifierChecks,
-            traversalState,
-          );
-        }
-      }
-    },
-  });
-}
-
-function matchCompilerDiagnostic(
-  badReference: NodePath<t.Node>,
-  transformErrors: Array<{fn: NodePath<t.Node>; error: CompilerError}>,
-): string | null {
-  for (const {fn, error} of transformErrors) {
-    if (fn.isAncestor(badReference)) {
-      return error.toString();
-    }
-  }
-  return null;
-}
--- a/compiler/packages/babel-plugin-react-compiler/src/Flood/FlowTypes.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/Flood/FlowTypes.ts
@@ -1,752 +0,0 @@
-/**
- * TypeScript definitions for Flow type JSON representations
- * Based on the output of /data/sandcastle/boxes/fbsource/fbcode/flow/src/typing/convertTypes.ml
- */
-
-// Base type for all Flow types with a kind field
-export interface BaseFlowType {
-  kind: string;
-}
-
-// Type for representing polarity
-export type Polarity = 'positive' | 'negative' | 'neutral';
-
-// Type for representing a name that might be null
-export type OptionalName = string | null;
-
-// Open type
-export interface OpenType extends BaseFlowType {
-  kind: 'Open';
-}
-
-// Def type
-export interface DefType extends BaseFlowType {
-  kind: 'Def';
-  def: DefT;
-}
-
-// Eval type
-export interface EvalType extends BaseFlowType {
-  kind: 'Eval';
-  type: FlowType;
-  destructor: Destructor;
-}
-
-// Generic type
-export interface GenericType extends BaseFlowType {
-  kind: 'Generic';
-  name: string;
-  bound: FlowType;
-  no_infer: boolean;
-}
-
-// ThisInstance type
-export interface ThisInstanceType extends BaseFlowType {
-  kind: 'ThisInstance';
-  instance: InstanceT;
-  is_this: boolean;
-  name: string;
-}
-
-// ThisTypeApp type
-export interface ThisTypeAppType extends BaseFlowType {
-  kind: 'ThisTypeApp';
-  t1: FlowType;
-  t2: FlowType;
-  t_list?: Array<FlowType>;
-}
-
-// TypeApp type
-export interface TypeAppType extends BaseFlowType {
-  kind: 'TypeApp';
-  type: FlowType;
-  targs: Array<FlowType>;
-  from_value: boolean;
-  use_desc: boolean;
-}
-
-// FunProto type
-export interface FunProtoType extends BaseFlowType {
-  kind: 'FunProto';
-}
-
-// ObjProto type
-export interface ObjProtoType extends BaseFlowType {
-  kind: 'ObjProto';
-}
-
-// NullProto type
-export interface NullProtoType extends BaseFlowType {
-  kind: 'NullProto';
-}
-
-// FunProtoBind type
-export interface FunProtoBindType extends BaseFlowType {
-  kind: 'FunProtoBind';
-}
-
-// Intersection type
-export interface IntersectionType extends BaseFlowType {
-  kind: 'Intersection';
-  members: Array<FlowType>;
-}
-
-// Union type
-export interface UnionType extends BaseFlowType {
-  kind: 'Union';
-  members: Array<FlowType>;
-}
-
-// Maybe type
-export interface MaybeType extends BaseFlowType {
-  kind: 'Maybe';
-  type: FlowType;
-}
-
-// Optional type
-export interface OptionalType extends BaseFlowType {
-  kind: 'Optional';
-  type: FlowType;
-  use_desc: boolean;
-}
-
-// Keys type
-export interface KeysType extends BaseFlowType {
-  kind: 'Keys';
-  type: FlowType;
-}
-
-// Annot type
-export interface AnnotType extends BaseFlowType {
-  kind: 'Annot';
-  type: FlowType;
-  use_desc: boolean;
-}
-
-// Opaque type
-export interface OpaqueType extends BaseFlowType {
-  kind: 'Opaque';
-  opaquetype: {
-    opaque_id: string;
-    underlying_t: FlowType | null;
-    super_t: FlowType | null;
-    opaque_type_args: Array<{
-      name: string;
-      type: FlowType;
-      polarity: Polarity;
-    }>;
-    opaque_name: string;
-  };
-}
-
-// Namespace type
-export interface NamespaceType extends BaseFlowType {
-  kind: 'Namespace';
-  namespace_symbol: {
-    symbol: string;
-  };
-  values_type: FlowType;
-  types_tmap: PropertyMap;
-}
-
-// Any type
-export interface AnyType extends BaseFlowType {
-  kind: 'Any';
-}
-
-// StrUtil type
-export interface StrUtilType extends BaseFlowType {
-  kind: 'StrUtil';
-  op: 'StrPrefix' | 'StrSuffix';
-  prefix?: string;
-  suffix?: string;
-  remainder?: FlowType;
-}
-
-// TypeParam definition
-export interface TypeParam {
-  name: string;
-  bound: FlowType;
-  polarity: Polarity;
-  default: FlowType | null;
-}
-
-// EnumInfo types
-export type EnumInfo = ConcreteEnum | AbstractEnum;
-
-export interface ConcreteEnum {
-  kind: 'ConcreteEnum';
-  enum_name: string;
-  enum_id: string;
-  members: Array<string>;
-  representation_t: FlowType;
-  has_unknown_members: boolean;
-}
-
-export interface AbstractEnum {
-  kind: 'AbstractEnum';
-  representation_t: FlowType;
-}
-
-// CanonicalRendersForm types
-export type CanonicalRendersForm =
-  | InstrinsicRenders
-  | NominalRenders
-  | StructuralRenders
-  | DefaultRenders;
-
-export interface InstrinsicRenders {
-  kind: 'InstrinsicRenders';
-  name: string;
-}
-
-export interface NominalRenders {
-  kind: 'NominalRenders';
-  renders_id: string;
-  renders_name: string;
-  renders_super: FlowType;
-}
-
-export interface StructuralRenders {
-  kind: 'StructuralRenders';
-  renders_variant: 'RendersNormal' | 'RendersMaybe' | 'RendersStar';
-  renders_structural_type: FlowType;
-}
-
-export interface DefaultRenders {
-  kind: 'DefaultRenders';
-}
-
-// InstanceT definition
-export interface InstanceT {
-  inst: InstType;
-  static: FlowType;
-  super: FlowType;
-  implements: Array<FlowType>;
-}
-
-// InstType definition
-export interface InstType {
-  class_name: string | null;
-  class_id: string;
-  type_args: Array<{
-    name: string;
-    type: FlowType;
-    polarity: Polarity;
-  }>;
-  own_props: PropertyMap;
-  proto_props: PropertyMap;
-  call_t: null | {
-    id: number;
-    call: FlowType;
-  };
-}
-
-// DefT types
-export type DefT =
-  | NumGeneralType
-  | StrGeneralType
-  | BoolGeneralType
-  | BigIntGeneralType
-  | EmptyType
-  | MixedType
-  | NullType
-  | VoidType
-  | SymbolType
-  | FunType
-  | ObjType
-  | ArrType
-  | ClassType
-  | InstanceType
-  | SingletonStrType
-  | NumericStrKeyType
-  | SingletonNumType
-  | SingletonBoolType
-  | SingletonBigIntType
-  | TypeType
-  | PolyType
-  | ReactAbstractComponentType
-  | RendersType
-  | EnumValueType
-  | EnumObjectType;
-
-export interface NumGeneralType extends BaseFlowType {
-  kind: 'NumGeneral';
-}
-
-export interface StrGeneralType extends BaseFlowType {
-  kind: 'StrGeneral';
-}
-
-export interface BoolGeneralType extends BaseFlowType {
-  kind: 'BoolGeneral';
-}
-
-export interface BigIntGeneralType extends BaseFlowType {
-  kind: 'BigIntGeneral';
-}
-
-export interface EmptyType extends BaseFlowType {
-  kind: 'Empty';
-}
-
-export interface MixedType extends BaseFlowType {
-  kind: 'Mixed';
-}
-
-export interface NullType extends BaseFlowType {
-  kind: 'Null';
-}
-
-export interface VoidType extends BaseFlowType {
-  kind: 'Void';
-}
-
-export interface SymbolType extends BaseFlowType {
-  kind: 'Symbol';
-}
-
-export interface FunType extends BaseFlowType {
-  kind: 'Fun';
-  static: FlowType;
-  funtype: FunTypeObj;
-}
-
-export interface ObjType extends BaseFlowType {
-  kind: 'Obj';
-  objtype: ObjTypeObj;
-}
-
-export interface ArrType extends BaseFlowType {
-  kind: 'Arr';
-  arrtype: ArrTypeObj;
-}
-
-export interface ClassType extends BaseFlowType {
-  kind: 'Class';
-  type: FlowType;
-}
-
-export interface InstanceType extends BaseFlowType {
-  kind: 'Instance';
-  instance: InstanceT;
-}
-
-export interface SingletonStrType extends BaseFlowType {
-  kind: 'SingletonStr';
-  from_annot: boolean;
-  value: string;
-}
-
-export interface NumericStrKeyType extends BaseFlowType {
-  kind: 'NumericStrKey';
-  number: string;
-  string: string;
-}
-
-export interface SingletonNumType extends BaseFlowType {
-  kind: 'SingletonNum';
-  from_annot: boolean;
-  number: string;
-  string: string;
-}
-
-export interface SingletonBoolType extends BaseFlowType {
-  kind: 'SingletonBool';
-  from_annot: boolean;
-  value: boolean;
-}
-
-export interface SingletonBigIntType extends BaseFlowType {
-  kind: 'SingletonBigInt';
-  from_annot: boolean;
-  value: string;
-}
-
-export interface TypeType extends BaseFlowType {
-  kind: 'Type';
-  type_kind: TypeTKind;
-  type: FlowType;
-}
-
-export type TypeTKind =
-  | 'TypeAliasKind'
-  | 'TypeParamKind'
-  | 'OpaqueKind'
-  | 'ImportTypeofKind'
-  | 'ImportClassKind'
-  | 'ImportEnumKind'
-  | 'InstanceKind'
-  | 'RenderTypeKind';
-
-export interface PolyType extends BaseFlowType {
-  kind: 'Poly';
-  tparams: Array<TypeParam>;
-  t_out: FlowType;
-  id: string;
-}
-
-export interface ReactAbstractComponentType extends BaseFlowType {
-  kind: 'ReactAbstractComponent';
-  config: FlowType;
-  renders: FlowType;
-  instance: ComponentInstance;
-  component_kind: ComponentKind;
-}
-
-export type ComponentInstance =
-  | {kind: 'RefSetterProp'; type: FlowType}
-  | {kind: 'Omitted'};
-
-export type ComponentKind =
-  | {kind: 'Structural'}
-  | {kind: 'Nominal'; id: string; name: string; types: Array<FlowType> | null};
-
-export interface RendersType extends BaseFlowType {
-  kind: 'Renders';
-  form: CanonicalRendersForm;
-}
-
-export interface EnumValueType extends BaseFlowType {
-  kind: 'EnumValue';
-  enum_info: EnumInfo;
-}
-
-export interface EnumObjectType extends BaseFlowType {
-  kind: 'EnumObject';
-  enum_value_t: FlowType;
-  enum_info: EnumInfo;
-}
-
-// ObjKind types
-export type ObjKind =
-  | {kind: 'Exact'}
-  | {kind: 'Inexact'}
-  | {kind: 'Indexed'; dicttype: DictType};
-
-// DictType definition
-export interface DictType {
-  dict_name: string | null;
-  key: FlowType;
-  value: FlowType;
-  dict_polarity: Polarity;
-}
-
-// ArrType types
-export type ArrTypeObj = ArrayAT | TupleAT | ROArrayAT;
-
-export interface ArrayAT {
-  kind: 'ArrayAT';
-  elem_t: FlowType;
-}
-
-export interface TupleAT {
-  kind: 'TupleAT';
-  elem_t: FlowType;
-  elements: Array<TupleElement>;
-  min_arity: number;
-  max_arity: number;
-  inexact: boolean;
-}
-
-export interface ROArrayAT {
-  kind: 'ROArrayAT';
-  elem_t: FlowType;
-}
-
-// TupleElement definition
-export interface TupleElement {
-  name: string | null;
-  t: FlowType;
-  polarity: Polarity;
-  optional: boolean;
-}
-
-// Flags definition
-export interface Flags {
-  obj_kind: ObjKind;
-}
-
-// Property types
-export type Property =
-  | FieldProperty
-  | GetProperty
-  | SetProperty
-  | GetSetProperty
-  | MethodProperty;
-
-export interface FieldProperty {
-  kind: 'Field';
-  type: FlowType;
-  polarity: Polarity;
-}
-
-export interface GetProperty {
-  kind: 'Get';
-  type: FlowType;
-}
-
-export interface SetProperty {
-  kind: 'Set';
-  type: FlowType;
-}
-
-export interface GetSetProperty {
-  kind: 'GetSet';
-  get_type: FlowType;
-  set_type: FlowType;
-}
-
-export interface MethodProperty {
-  kind: 'Method';
-  type: FlowType;
-}
-
-// PropertyMap definition
-export interface PropertyMap {
-  [key: string]: Property; // For other properties in the map
-}
-
-// ObjType definition
-export interface ObjTypeObj {
-  flags: Flags;
-  props: PropertyMap;
-  proto_t: FlowType;
-  call_t: number | null;
-}
-
-// FunType definition
-export interface FunTypeObj {
-  this_t: {
-    type: FlowType;
-    status: ThisStatus;
-  };
-  params: Array<{
-    name: string | null;
-    type: FlowType;
-  }>;
-  rest_param: null | {
-    name: string | null;
-    type: FlowType;
-  };
-  return_t: FlowType;
-  type_guard: null | {
-    inferred: boolean;
-    param_name: string;
-    type_guard: FlowType;
-    one_sided: boolean;
-  };
-  effect: Effect;
-}
-
-// ThisStatus types
-export type ThisStatus =
-  | {kind: 'This_Method'; unbound: boolean}
-  | {kind: 'This_Function'};
-
-// Effect types
-export type Effect =
-  | {kind: 'HookDecl'; id: string}
-  | {kind: 'HookAnnot'}
-  | {kind: 'ArbitraryEffect'}
-  | {kind: 'AnyEffect'};
-
-// Destructor types
-export type Destructor =
-  | NonMaybeTypeDestructor
-  | PropertyTypeDestructor
-  | ElementTypeDestructor
-  | OptionalIndexedAccessNonMaybeTypeDestructor
-  | OptionalIndexedAccessResultTypeDestructor
-  | ExactTypeDestructor
-  | ReadOnlyTypeDestructor
-  | PartialTypeDestructor
-  | RequiredTypeDestructor
-  | SpreadTypeDestructor
-  | SpreadTupleTypeDestructor
-  | RestTypeDestructor
-  | ValuesTypeDestructor
-  | ConditionalTypeDestructor
-  | TypeMapDestructor
-  | ReactElementPropsTypeDestructor
-  | ReactElementConfigTypeDestructor
-  | ReactCheckComponentConfigDestructor
-  | ReactDRODestructor
-  | MakeHooklikeDestructor
-  | MappedTypeDestructor
-  | EnumTypeDestructor;
-
-export interface NonMaybeTypeDestructor {
-  kind: 'NonMaybeType';
-}
-
-export interface PropertyTypeDestructor {
-  kind: 'PropertyType';
-  name: string;
-}
-
-export interface ElementTypeDestructor {
-  kind: 'ElementType';
-  index_type: FlowType;
-}
-
-export interface OptionalIndexedAccessNonMaybeTypeDestructor {
-  kind: 'OptionalIndexedAccessNonMaybeType';
-  index: OptionalIndexedAccessIndex;
-}
-
-export type OptionalIndexedAccessIndex =
-  | {kind: 'StrLitIndex'; name: string}
-  | {kind: 'TypeIndex'; type: FlowType};
-
-export interface OptionalIndexedAccessResultTypeDestructor {
-  kind: 'OptionalIndexedAccessResultType';
-}
-
-export interface ExactTypeDestructor {
-  kind: 'ExactType';
-}
-
-export interface ReadOnlyTypeDestructor {
-  kind: 'ReadOnlyType';
-}
-
-export interface PartialTypeDestructor {
-  kind: 'PartialType';
-}
-
-export interface RequiredTypeDestructor {
-  kind: 'RequiredType';
-}
-
-export interface SpreadTypeDestructor {
-  kind: 'SpreadType';
-  target: SpreadTarget;
-  operands: Array<SpreadOperand>;
-  operand_slice: Slice | null;
-}
-
-export type SpreadTarget =
-  | {kind: 'Value'; make_seal: 'Sealed' | 'Frozen' | 'As_Const'}
-  | {kind: 'Annot'; make_exact: boolean};
-
-export type SpreadOperand = {kind: 'Type'; type: FlowType} | Slice;
-
-export interface Slice {
-  kind: 'Slice';
-  prop_map: PropertyMap;
-  generics: Array<string>;
-  dict: DictType | null;
-  reachable_targs: Array<{
-    type: FlowType;
-    polarity: Polarity;
-  }>;
-}
-
-export interface SpreadTupleTypeDestructor {
-  kind: 'SpreadTupleType';
-  inexact: boolean;
-  resolved_rev: string;
-  unresolved: string;
-}
-
-export interface RestTypeDestructor {
-  kind: 'RestType';
-  merge_mode: RestMergeMode;
-  type: FlowType;
-}
-
-export type RestMergeMode =
-  | {kind: 'SpreadReversal'}
-  | {kind: 'ReactConfigMerge'; polarity: Polarity}
-  | {kind: 'Omit'};
-
-export interface ValuesTypeDestructor {
-  kind: 'ValuesType';
-}
-
-export interface ConditionalTypeDestructor {
-  kind: 'ConditionalType';
-  distributive_tparam_name: string | null;
-  infer_tparams: string;
-  extends_t: FlowType;
-  true_t: FlowType;
-  false_t: FlowType;
-}
-
-export interface TypeMapDestructor {
-  kind: 'ObjectKeyMirror';
-}
-
-export interface ReactElementPropsTypeDestructor {
-  kind: 'ReactElementPropsType';
-}
-
-export interface ReactElementConfigTypeDestructor {
-  kind: 'ReactElementConfigType';
-}
-
-export interface ReactCheckComponentConfigDestructor {
-  kind: 'ReactCheckComponentConfig';
-  props: {
-    [key: string]: Property;
-  };
-}
-
-export interface ReactDRODestructor {
-  kind: 'ReactDRO';
-  dro_type:
-    | 'HookReturn'
-    | 'HookArg'
-    | 'Props'
-    | 'ImmutableAnnot'
-    | 'DebugAnnot';
-}
-
-export interface MakeHooklikeDestructor {
-  kind: 'MakeHooklike';
-}
-
-export interface MappedTypeDestructor {
-  kind: 'MappedType';
-  homomorphic: Homomorphic;
-  distributive_tparam_name: string | null;
-  property_type: FlowType;
-  mapped_type_flags: {
-    variance: Polarity;
-    optional: 'MakeOptional' | 'RemoveOptional' | 'KeepOptionality';
-  };
-}
-
-export type Homomorphic =
-  | {kind: 'Homomorphic'}
-  | {kind: 'Unspecialized'}
-  | {kind: 'SemiHomomorphic'; type: FlowType};
-
-export interface EnumTypeDestructor {
-  kind: 'EnumType';
-}
-
-// Union of all possible Flow types
-export type FlowType =
-  | OpenType
-  | DefType
-  | EvalType
-  | GenericType
-  | ThisInstanceType
-  | ThisTypeAppType
-  | TypeAppType
-  | FunProtoType
-  | ObjProtoType
-  | NullProtoType
-  | FunProtoBindType
-  | IntersectionType
-  | UnionType
-  | MaybeType
-  | OptionalType
-  | KeysType
-  | AnnotType
-  | OpaqueType
-  | NamespaceType
-  | AnyType
-  | StrUtilType;
--- a/compiler/packages/babel-plugin-react-compiler/src/Flood/TypeErrors.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/Flood/TypeErrors.ts
@@ -1,138 +0,0 @@
-import {CompilerError, SourceLocation} from '..';
-import {
-  ConcreteType,
-  printConcrete,
-  printType,
-  StructuralValue,
-  Type,
-  VariableId,
-} from './Types';
-
-export function unsupportedLanguageFeature(
-  desc: string,
-  loc: SourceLocation,
-): never {
-  CompilerError.throwInvalidJS({
-    reason: `Typedchecker does not currently support language feature: ${desc}`,
-    loc,
-  });
-}
-
-export type UnificationError =
-  | {
-      kind: 'TypeUnification';
-      left: ConcreteType<Type>;
-      right: ConcreteType<Type>;
-    }
-  | {
-      kind: 'StructuralUnification';
-      left: StructuralValue;
-      right: ConcreteType<Type>;
-    };
-
-function printUnificationError(err: UnificationError): string {
-  if (err.kind === 'TypeUnification') {
-    return `${printConcrete(err.left, printType)} is incompatible with ${printConcrete(err.right, printType)}`;
-  } else {
-    return `structural ${err.left.kind} is incompatible with ${printConcrete(err.right, printType)}`;
-  }
-}
-
-export function raiseUnificationErrors(
-  errs: null | Array<UnificationError>,
-  loc: SourceLocation,
-): void {
-  if (errs != null) {
-    if (errs.length === 0) {
-      CompilerError.invariant(false, {
-        reason: 'Should not have array of zero errors',
-        description: null,
-        details: [
-          {
-            kind: 'error',
-            loc,
-            message: null,
-          },
-        ],
-      });
-    } else if (errs.length === 1) {
-      CompilerError.throwInvalidJS({
-        reason: `Unable to unify types because ${printUnificationError(errs[0])}`,
-        loc,
-      });
-    } else {
-      const messages = errs
-        .map(err => `\t* ${printUnificationError(err)}`)
-        .join('\n');
-      CompilerError.throwInvalidJS({
-        reason: `Unable to unify types because:\n${messages}`,
-        loc,
-      });
-    }
-  }
-}
-
-export function unresolvableTypeVariable(
-  id: VariableId,
-  loc: SourceLocation,
-): never {
-  CompilerError.throwInvalidJS({
-    reason: `Unable to resolve free variable ${id} to a concrete type`,
-    loc,
-  });
-}
-
-export function cannotAddVoid(explicit: boolean, loc: SourceLocation): never {
-  if (explicit) {
-    CompilerError.throwInvalidJS({
-      reason: `Undefined is not a valid operand of \`+\``,
-      loc,
-    });
-  } else {
-    CompilerError.throwInvalidJS({
-      reason: `Value may be undefined, which is not a valid operand of \`+\``,
-      loc,
-    });
-  }
-}
-
-export function unsupportedTypeAnnotation(
-  desc: string,
-  loc: SourceLocation,
-): never {
-  CompilerError.throwInvalidJS({
-    reason: `Typedchecker does not currently support type annotation: ${desc}`,
-    loc,
-  });
-}
-
-export function checkTypeArgumentArity(
-  desc: string,
-  expected: number,
-  actual: number,
-  loc: SourceLocation,
-): void {
-  if (expected !== actual) {
-    CompilerError.throwInvalidJS({
-      reason: `Expected ${desc} to have ${expected} type parameters, got ${actual}`,
-      loc,
-    });
-  }
-}
-
-export function notAFunction(desc: string, loc: SourceLocation): void {
-  CompilerError.throwInvalidJS({
-    reason: `Cannot call ${desc} because it is not a function`,
-    loc,
-  });
-}
-
-export function notAPolymorphicFunction(
-  desc: string,
-  loc: SourceLocation,
-): void {
-  CompilerError.throwInvalidJS({
-    reason: `Cannot call ${desc} with type arguments because it is not a polymorphic function`,
-    loc,
-  });
-}
--- a/compiler/packages/babel-plugin-react-compiler/src/Flood/TypeUtils.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/Flood/TypeUtils.ts
@@ -1,312 +0,0 @@
-import {GeneratedSource} from '../HIR';
-import {assertExhaustive} from '../Utils/utils';
-import {unsupportedLanguageFeature} from './TypeErrors';
-import {
-  ConcreteType,
-  ResolvedType,
-  TypeParameter,
-  TypeParameterId,
-  DEBUG,
-  printConcrete,
-  printType,
-} from './Types';
-
-export function substitute(
-  type: ConcreteType<ResolvedType>,
-  typeParameters: Array<TypeParameter<ResolvedType>>,
-  typeArguments: Array<ResolvedType>,
-): ResolvedType {
-  const substMap = new Map<TypeParameterId, ResolvedType>();
-  for (let i = 0; i < typeParameters.length; i++) {
-    // TODO: Length checks to make sure type params match up with args
-    const typeParameter = typeParameters[i];
-    const typeArgument = typeArguments[i];
-    substMap.set(typeParameter.id, typeArgument);
-  }
-  const substitutionFunction = (t: ResolvedType): ResolvedType => {
-    // TODO: We really want a stateful mapper or visitor here so that we can model nested polymorphic types
-    if (t.type.kind === 'Generic' && substMap.has(t.type.id)) {
-      const substitutedType = substMap.get(t.type.id)!;
-      return substitutedType;
-    }
-
-    return {
-      kind: 'Concrete',
-      type: mapType(substitutionFunction, t.type),
-      platform: t.platform,
-    };
-  };
-
-  const substituted = mapType(substitutionFunction, type);
-
-  if (DEBUG) {
-    let substs = '';
-    for (let i = 0; i < typeParameters.length; i++) {
-      const typeParameter = typeParameters[i];
-      const typeArgument = typeArguments[i];
-      substs += `[${typeParameter.name}${typeParameter.id} := ${printType(typeArgument)}]`;
-    }
-    console.log(
-      `${printConcrete(type, printType)}${substs} = ${printConcrete(substituted, printType)}`,
-    );
-  }
-
-  return {kind: 'Concrete', type: substituted, platform: /* TODO */ 'shared'};
-}
-
-export function mapType<T, U>(
-  f: (t: T) => U,
-  type: ConcreteType<T>,
-): ConcreteType<U> {
-  switch (type.kind) {
-    case 'Mixed':
-    case 'Number':
-    case 'String':
-    case 'Boolean':
-    case 'Void':
-      return type;
-
-    case 'Nullable':
-      return {
-        kind: 'Nullable',
-        type: f(type.type),
-      };
-
-    case 'Array':
-      return {
-        kind: 'Array',
-        element: f(type.element),
-      };
-
-    case 'Set':
-      return {
-        kind: 'Set',
-        element: f(type.element),
-      };
-
-    case 'Map':
-      return {
-        kind: 'Map',
-        key: f(type.key),
-        value: f(type.value),
-      };
-
-    case 'Function':
-      return {
-        kind: 'Function',
-        typeParameters:
-          type.typeParameters?.map(param => ({
-            id: param.id,
-            name: param.name,
-            bound: f(param.bound),
-          })) ?? null,
-        params: type.params.map(f),
-        returnType: f(type.returnType),
-      };
-
-    case 'Component': {
-      return {
-        kind: 'Component',
-        children: type.children != null ? f(type.children) : null,
-        props: new Map([...type.props.entries()].map(([k, v]) => [k, f(v)])),
-      };
-    }
-
-    case 'Generic':
-      return {
-        kind: 'Generic',
-        id: type.id,
-        bound: f(type.bound),
-      };
-
-    case 'Object':
-      return type;
-
-    case 'Tuple':
-      return {
-        kind: 'Tuple',
-        id: type.id,
-        members: type.members.map(f),
-      };
-
-    case 'Structural':
-      return type;
-
-    case 'Enum':
-    case 'Union':
-    case 'Instance':
-      unsupportedLanguageFeature(type.kind, GeneratedSource);
-
-    default:
-      assertExhaustive(type, 'Unknown type kind');
-  }
-}
-
-export function diff<R, T>(
-  a: ConcreteType<T>,
-  b: ConcreteType<T>,
-  onChild: (a: T, b: T) => R,
-  onChildMismatch: (child: R, cur: R) => R,
-  onMismatch: (a: ConcreteType<T>, b: ConcreteType<T>, cur: R) => R,
-  init: R,
-): R {
-  let errors = init;
-
-  // Check if kinds match
-  if (a.kind !== b.kind) {
-    errors = onMismatch(a, b, errors);
-    return errors;
-  }
-
-  // Based on kind, check other properties
-  switch (a.kind) {
-    case 'Mixed':
-    case 'Number':
-    case 'String':
-    case 'Boolean':
-    case 'Void':
-      // Simple types, no further checks needed
-      break;
-
-    case 'Nullable':
-      // Check the nested type
-      errors = onChildMismatch(onChild(a.type, (b as typeof a).type), errors);
-      break;
-
-    case 'Array':
-    case 'Set':
-      // Check the element type
-      errors = onChildMismatch(
-        onChild(a.element, (b as typeof a).element),
-        errors,
-      );
-      break;
-
-    case 'Map':
-      // Check both key and value types
-      errors = onChildMismatch(onChild(a.key, (b as typeof a).key), errors);
-      errors = onChildMismatch(onChild(a.value, (b as typeof a).value), errors);
-      break;
-
-    case 'Function': {
-      const bFunc = b as typeof a;
-
-      // Check type parameters
-      if ((a.typeParameters == null) !== (bFunc.typeParameters == null)) {
-        errors = onMismatch(a, b, errors);
-      }
-
-      if (a.typeParameters != null && bFunc.typeParameters != null) {
-        if (a.typeParameters.length !== bFunc.typeParameters.length) {
-          errors = onMismatch(a, b, errors);
-        }
-
-        // Type parameters are just numbers, so we can compare them directly
-        for (let i = 0; i < a.typeParameters.length; i++) {
-          if (a.typeParameters[i] !== bFunc.typeParameters[i]) {
-            errors = onMismatch(a, b, errors);
-          }
-        }
-      }
-
-      // Check parameters
-      if (a.params.length !== bFunc.params.length) {
-        errors = onMismatch(a, b, errors);
-      }
-
-      for (let i = 0; i < a.params.length; i++) {
-        errors = onChildMismatch(onChild(a.params[i], bFunc.params[i]), errors);
-      }
-
-      // Check return type
-      errors = onChildMismatch(onChild(a.returnType, bFunc.returnType), errors);
-      break;
-    }
-
-    case 'Component': {
-      const bComp = b as typeof a;
-
-      // Check children
-      if (a.children !== bComp.children) {
-        errors = onMismatch(a, b, errors);
-      }
-
-      // Check props
-      if (a.props.size !== bComp.props.size) {
-        errors = onMismatch(a, b, errors);
-      }
-
-      for (const [k, v] of a.props) {
-        const bProp = bComp.props.get(k);
-        if (bProp == null) {
-          errors = onMismatch(a, b, errors);
-        } else {
-          errors = onChildMismatch(onChild(v, bProp), errors);
-        }
-      }
-
-      break;
-    }
-
-    case 'Generic': {
-      // Check that the type parameter IDs match
-      if (a.id !== (b as typeof a).id) {
-        errors = onMismatch(a, b, errors);
-      }
-      break;
-    }
-    case 'Structural': {
-      const bStruct = b as typeof a;
-
-      // Check that the structural IDs match
-      if (a.id !== bStruct.id) {
-        errors = onMismatch(a, b, errors);
-      }
-      break;
-    }
-    case 'Object': {
-      const bNom = b as typeof a;
-
-      // Check that the nominal IDs match
-      if (a.id !== bNom.id) {
-        errors = onMismatch(a, b, errors);
-      }
-      break;
-    }
-
-    case 'Tuple': {
-      const bTuple = b as typeof a;
-
-      // Check that the tuple IDs match
-      if (a.id !== bTuple.id) {
-        errors = onMismatch(a, b, errors);
-      }
-      for (let i = 0; i < a.members.length; i++) {
-        errors = onChildMismatch(
-          onChild(a.members[i], bTuple.members[i]),
-          errors,
-        );
-      }
-
-      break;
-    }
-
-    case 'Enum':
-    case 'Instance':
-    case 'Union': {
-      unsupportedLanguageFeature(a.kind, GeneratedSource);
-    }
-
-    default:
-      assertExhaustive(a, 'Unknown type kind');
-  }
-
-  return errors;
-}
-
-export function filterOptional(t: ResolvedType): ResolvedType {
-  if (t.kind === 'Concrete' && t.type.kind === 'Nullable') {
-    return t.type.type;
-  }
-  return t;
-}
--- a/compiler/packages/babel-plugin-react-compiler/src/Flood/Types.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/Flood/Types.ts
--- a/compiler/packages/babel-plugin-react-compiler/src/HIR/AssertConsistentIdentifiers.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/HIR/AssertConsistentIdentifiers.ts
@@ -38,13 +38,7 @@ export function assertConsistentIdentifiers(fn: HIRFunction): void {
      CompilerError.invariant(instr.lvalue.identifier.name === null, {
        reason: `Expected all lvalues to be temporaries`,
        description: `Found named lvalue \`${instr.lvalue.identifier.name}\``,
-        details: [
-          {
-            kind: 'error',
-            loc: instr.lvalue.loc,
-            message: null,
-          },
-        ],
+        loc: instr.lvalue.loc,
        suggestions: null,
      });
      CompilerError.invariant(!assignments.has(instr.lvalue.identifier.id), {
@@ -52,13 +46,7 @@ export function assertConsistentIdentifiers(fn: HIRFunction): void {
        description: `Found duplicate assignment of '${printPlace(
          instr.lvalue,
        )}'`,
-        details: [
-          {
-            kind: 'error',
-            loc: instr.lvalue.loc,
-            message: null,
-          },
-        ],
+        loc: instr.lvalue.loc,
        suggestions: null,
      });
      assignments.add(instr.lvalue.identifier.id);
@@ -89,13 +77,7 @@ function validate(
    CompilerError.invariant(identifier === previous, {
      reason: `Duplicate identifier object`,
      description: `Found duplicate identifier object for id ${identifier.id}`,
-      details: [
-        {
-          kind: 'error',
-          loc: loc ?? GeneratedSource,
-          message: null,
-        },
-      ],
+      loc: loc ?? GeneratedSource,
      suggestions: null,
    });
  }
--- a/compiler/packages/babel-plugin-react-compiler/src/HIR/AssertTerminalBlocksExist.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/HIR/AssertTerminalBlocksExist.ts
@@ -18,13 +18,7 @@ export function assertTerminalSuccessorsExist(fn: HIRFunction): void {
        description: `Block bb${successor} does not exist for terminal '${printTerminal(
          block.terminal,
        )}'`,
-        details: [
-          {
-            kind: 'error',
-            loc: (block.terminal as any).loc ?? GeneratedSource,
-            message: null,
-          },
-        ],
+        loc: (block.terminal as any).loc ?? GeneratedSource,
        suggestions: null,
      });
      return successor;
@@ -39,26 +33,14 @@ export function assertTerminalPredsExist(fn: HIRFunction): void {
      CompilerError.invariant(predBlock != null, {
        reason: 'Expected predecessor block to exist',
        description: `Block ${block.id} references non-existent ${pred}`,
-        details: [
-          {
-            kind: 'error',
-            loc: GeneratedSource,
-            message: null,
-          },
-        ],
+        loc: GeneratedSource,
      });
      CompilerError.invariant(
        [...eachTerminalSuccessor(predBlock.terminal)].includes(block.id),
        {
          reason: 'Terminal successor does not reference correct predecessor',
          description: `Block bb${block.id} has bb${predBlock.id} as a predecessor, but bb${predBlock.id}'s successors do not include bb${block.id}`,
-          details: [
-            {
-              kind: 'error',
-              loc: GeneratedSource,
-              message: null,
-            },
-          ],
+          loc: GeneratedSource,
        },
      );
    }
--- a/compiler/packages/babel-plugin-react-compiler/src/HIR/AssertValidBlockNesting.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/HIR/AssertValidBlockNesting.ts
@@ -1,10 +1,3 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
 import {CompilerError} from '..';
 import {
  BlockId,
@@ -131,13 +124,7 @@ export function recursivelyTraverseItems<T, TContext>(
      CompilerError.invariant(disjoint || nested, {
        reason: 'Invalid nesting in program blocks or scopes',
        description: `Items overlap but are not nested: ${maybeParentRange.start}:${maybeParentRange.end}(${currRange.start}:${currRange.end})`,
-        details: [
-          {
-            kind: 'error',
-            loc: GeneratedSource,
-            message: null,
-          },
-        ],
+        loc: GeneratedSource,
      });
      if (disjoint) {
        exit(maybeParent, context);
--- a/compiler/packages/babel-plugin-react-compiler/src/HIR/AssertValidMutableRanges.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/HIR/AssertValidMutableRanges.ts
@@ -5,14 +5,13 @@
 * LICENSE file in the root directory of this source tree.
 */

-import {HIRFunction, MutableRange, Place} from './HIR';
+import invariant from 'invariant';
+import {HIRFunction, Identifier, MutableRange} from './HIR';
 import {
  eachInstructionLValue,
  eachInstructionOperand,
  eachTerminalOperand,
 } from './visitors';
-import {CompilerError} from '..';
-import {printPlace} from './PrintHIR';

 /*
 * Checks that all mutable ranges in the function are well-formed, with
@@ -21,49 +20,38 @@ import {printPlace} from './PrintHIR';
 export function assertValidMutableRanges(fn: HIRFunction): void {
  for (const [, block] of fn.body.blocks) {
    for (const phi of block.phis) {
-      visit(phi.place, `phi for block bb${block.id}`);
-      for (const [pred, operand] of phi.operands) {
-        visit(operand, `phi predecessor bb${pred} for block bb${block.id}`);
+      visitIdentifier(phi.place.identifier);
+      for (const [, operand] of phi.operands) {
+        visitIdentifier(operand.identifier);
      }
    }
    for (const instr of block.instructions) {
      for (const operand of eachInstructionLValue(instr)) {
-        visit(operand, `instruction [${instr.id}]`);
+        visitIdentifier(operand.identifier);
      }
      for (const operand of eachInstructionOperand(instr)) {
-        visit(operand, `instruction [${instr.id}]`);
+        visitIdentifier(operand.identifier);
      }
    }
    for (const operand of eachTerminalOperand(block.terminal)) {
-      visit(operand, `terminal [${block.terminal.id}]`);
+      visitIdentifier(operand.identifier);
    }
  }
 }

-function visit(place: Place, description: string): void {
-  validateMutableRange(place, place.identifier.mutableRange, description);
-  if (place.identifier.scope !== null) {
-    validateMutableRange(place, place.identifier.scope.range, description);
+function visitIdentifier(identifier: Identifier): void {
+  validateMutableRange(identifier.mutableRange);
+  if (identifier.scope !== null) {
+    validateMutableRange(identifier.scope.range);
  }
 }

-function validateMutableRange(
-  place: Place,
-  range: MutableRange,
-  description: string,
-): void {
-  CompilerError.invariant(
-    (range.start === 0 && range.end === 0) || range.end > range.start,
-    {
-      reason: `Invalid mutable range: [${range.start}:${range.end}]`,
-      description: `${printPlace(place)} in ${description}`,
-      details: [
-        {
-          kind: 'error',
-          loc: place.loc,
-          message: null,
-        },
-      ],
-    },
+function validateMutableRange(mutableRange: MutableRange): void {
+  invariant(
+    (mutableRange.start === 0 && mutableRange.end === 0) ||
+      mutableRange.end > mutableRange.start,
+    'Identifier scope mutableRange was invalid: [%s:%s]',
+    mutableRange.start,
+    mutableRange.end,
  );
 }
--- a/compiler/packages/babel-plugin-react-compiler/src/HIR/BuildHIR.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/HIR/BuildHIR.ts
--- a/compiler/packages/babel-plugin-react-compiler/src/HIR/BuildReactiveScopeTerminalsHIR.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/HIR/BuildReactiveScopeTerminalsHIR.ts
@@ -1,10 +1,3 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
 import {CompilerError} from '../CompilerError';
 import {getScopes, recursivelyTraverseItems} from './AssertValidBlockNesting';
 import {Environment} from './Environment';
@@ -234,14 +227,7 @@ function pushEndScopeTerminal(
  const fallthroughId = context.fallthroughs.get(scope.id);
  CompilerError.invariant(fallthroughId != null, {
    reason: 'Expected scope to exist',
-    description: null,
-    details: [
-      {
-        kind: 'error',
-        loc: GeneratedSource,
-        message: null,
-      },
-    ],
+    loc: GeneratedSource,
  });
  context.rewrites.push({
    kind: 'EndScope',
--- a/compiler/packages/babel-plugin-react-compiler/src/HIR/CollectHoistablePropertyLoads.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/HIR/CollectHoistablePropertyLoads.ts
@@ -1,10 +1,3 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
 import {CompilerError} from '../CompilerError';
 import {inRange} from '../ReactiveScopes/InferReactiveScopeVariables';
 import {printDependency} from '../ReactiveScopes/PrintReactiveFunction';
@@ -19,19 +12,15 @@ import {
  BasicBlock,
  BlockId,
  DependencyPathEntry,
-  FunctionExpression,
  GeneratedSource,
-  getHookKind,
  HIRFunction,
  Identifier,
  IdentifierId,
  InstructionId,
  InstructionValue,
-  LoweredFunction,
  PropertyLiteral,
  ReactiveScopeDependency,
  ScopeId,
-  TInstruction,
 } from './HIR';

 const DEBUG_PRINT = false;
@@ -123,39 +112,9 @@ export function collectHoistablePropertyLoads(
    hoistableFromOptionals,
    registry,
    nestedFnImmutableContext: null,
-    assumedInvokedFns: fn.env.config.enableTreatFunctionDepsAsConditional
-      ? new Set()
-      : getAssumedInvokedFunctions(fn),
  });
 }

-export function collectHoistablePropertyLoadsInInnerFn(
-  fnInstr: TInstruction<FunctionExpression>,
-  temporaries: ReadonlyMap<IdentifierId, ReactiveScopeDependency>,
-  hoistableFromOptionals: ReadonlyMap<BlockId, ReactiveScopeDependency>,
-): ReadonlyMap<BlockId, BlockInfo> {
-  const fn = fnInstr.value.loweredFunc.func;
-  const initialContext: CollectHoistablePropertyLoadsContext = {
-    temporaries,
-    knownImmutableIdentifiers: new Set(),
-    hoistableFromOptionals,
-    registry: new PropertyPathRegistry(),
-    nestedFnImmutableContext: null,
-    assumedInvokedFns: fn.env.config.enableTreatFunctionDepsAsConditional
-      ? new Set()
-      : getAssumedInvokedFunctions(fn),
-  };
-  const nestedFnImmutableContext = new Set(
-    fn.context
-      .filter(place =>
-        isImmutableAtInstr(place.identifier, fnInstr.id, initialContext),
-      )
-      .map(place => place.identifier.id),
-  );
-  initialContext.nestedFnImmutableContext = nestedFnImmutableContext;
-  return collectHoistablePropertyLoadsImpl(fn, initialContext);
-}
-
 type CollectHoistablePropertyLoadsContext = {
  temporaries: ReadonlyMap<IdentifierId, ReactiveScopeDependency>;
  knownImmutableIdentifiers: ReadonlySet<IdentifierId>;
@@ -168,11 +127,6 @@ type CollectHoistablePropertyLoadsContext = {
   * but are currently kept separate for readability.
   */
  nestedFnImmutableContext: ReadonlySet<IdentifierId> | null;
-  /**
-   * Functions which are assumed to be eventually called (as opposed to ones which might
-   * not be called, e.g. the 0th argument of Array.map)
-   */
-  assumedInvokedFns: ReadonlySet<LoweredFunction>;
 };
 function collectHoistablePropertyLoadsImpl(
  fn: HIRFunction,
@@ -241,10 +195,7 @@ type PropertyPathNode =
 class PropertyPathRegistry {
  roots: Map<IdentifierId, RootNode> = new Map();

-  getOrCreateIdentifier(
-    identifier: Identifier,
-    reactive: boolean,
-  ): PropertyPathNode {
+  getOrCreateIdentifier(identifier: Identifier): PropertyPathNode {
    /**
     * Reads from a statically scoped variable are always safe in JS,
     * with the exception of TDZ (not addressed by this pass).
@@ -258,26 +209,12 @@ class PropertyPathRegistry {
        optionalProperties: new Map(),
        fullPath: {
          identifier,
-          reactive,
          path: [],
        },
        hasOptional: false,
        parent: null,
      };
      this.roots.set(identifier.id, rootNode);
-    } else {
-      CompilerError.invariant(reactive === rootNode.fullPath.reactive, {
-        reason:
-          '[HoistablePropertyLoads] Found inconsistencies in `reactive` flag when deduping identifier reads within the same scope',
-        description: null,
-        details: [
-          {
-            kind: 'error',
-            loc: identifier.loc,
-            message: null,
-          },
-        ],
-      });
    }
    return rootNode;
  }
@@ -295,7 +232,6 @@ class PropertyPathRegistry {
        parent: parent,
        fullPath: {
          identifier: parent.fullPath.identifier,
-          reactive: parent.fullPath.reactive,
          path: parent.fullPath.path.concat(entry),
        },
        hasOptional: parent.hasOptional || entry.optional,
@@ -311,7 +247,7 @@ class PropertyPathRegistry {
     * so all subpaths of a PropertyLoad should already exist
     * (e.g. a.b is added before a.b.c),
     */
-    let currNode = this.getOrCreateIdentifier(n.identifier, n.reactive);
+    let currNode = this.getOrCreateIdentifier(n.identifier);
    if (n.path.length === 0) {
      return currNode;
    }
@@ -333,11 +269,10 @@ function getMaybeNonNullInInstruction(
  instr: InstructionValue,
  context: CollectHoistablePropertyLoadsContext,
 ): PropertyPathNode | null {
-  let path: ReactiveScopeDependency | null = null;
+  let path = null;
  if (instr.kind === 'PropertyLoad') {
    path = context.temporaries.get(instr.object.identifier.id) ?? {
      identifier: instr.object.identifier,
-      reactive: instr.object.reactive,
      path: [],
    };
  } else if (instr.kind === 'Destructure') {
@@ -400,16 +335,10 @@ function collectNonNullsInBlocks(
  ) {
    const identifier = fn.params[0].identifier;
    knownNonNullIdentifiers.add(
-      context.registry.getOrCreateIdentifier(identifier, true),
+      context.registry.getOrCreateIdentifier(identifier),
    );
  }
-  const nodes = new Map<
-    BlockId,
-    {
-      block: BasicBlock;
-      assumedNonNullObjects: Set<PropertyPathNode>;
-    }
-  >();
+  const nodes = new Map<BlockId, BlockInfo>();
  for (const [_, block] of fn.body.blocks) {
    const assumedNonNullObjects = new Set<PropertyPathNode>(
      knownNonNullIdentifiers,
@@ -429,30 +358,32 @@ function collectNonNullsInBlocks(
      ) {
        assumedNonNullObjects.add(maybeNonNull);
      }
-      if (instr.value.kind === 'FunctionExpression') {
+      if (
+        (instr.value.kind === 'FunctionExpression' ||
+          instr.value.kind === 'ObjectMethod') &&
+        !fn.env.config.enableTreatFunctionDepsAsConditional
+      ) {
        const innerFn = instr.value.loweredFunc;
-        if (context.assumedInvokedFns.has(innerFn)) {
-          const innerHoistableMap = collectHoistablePropertyLoadsImpl(
-            innerFn.func,
-            {
-              ...context,
-              nestedFnImmutableContext:
-                context.nestedFnImmutableContext ??
-                new Set(
-                  innerFn.func.context
-                    .filter(place =>
-                      isImmutableAtInstr(place.identifier, instr.id, context),
-                    )
-                    .map(place => place.identifier.id),
-                ),
-            },
-          );
-          const innerHoistables = assertNonNull(
-            innerHoistableMap.get(innerFn.func.body.entry),
-          );
-          for (const entry of innerHoistables.assumedNonNullObjects) {
-            assumedNonNullObjects.add(entry);
-          }
+        const innerHoistableMap = collectHoistablePropertyLoadsImpl(
+          innerFn.func,
+          {
+            ...context,
+            nestedFnImmutableContext:
+              context.nestedFnImmutableContext ??
+              new Set(
+                innerFn.func.context
+                  .filter(place =>
+                    isImmutableAtInstr(place.identifier, instr.id, context),
+                  )
+                  .map(place => place.identifier.id),
+              ),
+          },
+        );
+        const innerHoistables = assertNonNull(
+          innerHoistableMap.get(innerFn.func.body.entry),
+        );
+        for (const entry of innerHoistables.assumedNonNullObjects) {
+          assumedNonNullObjects.add(entry);
        }
      }
    }
@@ -505,14 +436,7 @@ function propagateNonNull(
    if (node == null) {
      CompilerError.invariant(false, {
        reason: `Bad node ${nodeId}, kind: ${direction}`,
-        description: null,
-        details: [
-          {
-            kind: 'error',
-            loc: GeneratedSource,
-            message: null,
-          },
-        ],
+        loc: GeneratedSource,
      });
    }
    const neighbors = Array.from(
@@ -584,14 +508,7 @@ function propagateNonNull(
    CompilerError.invariant(i++ < 100, {
      reason:
        '[CollectHoistablePropertyLoads] fixed point iteration did not terminate after 100 loops',
-      description: null,
-      details: [
-        {
-          kind: 'error',
-          loc: GeneratedSource,
-          message: null,
-        },
-      ],
+      loc: GeneratedSource,
    });

    changed = false;
@@ -623,13 +540,7 @@ export function assertNonNull<T extends NonNullable<U>, U>(
  CompilerError.invariant(value != null, {
    reason: 'Unexpected null',
    description: source != null ? `(from ${source})` : null,
-    details: [
-      {
-        kind: 'error',
-        loc: GeneratedSource,
-        message: null,
-      },
-    ],
+    loc: GeneratedSource,
  });
  return value;
 }
@@ -655,11 +566,9 @@ function reduceMaybeOptionalChains(
    changed = false;

    for (const original of optionalChainNodes) {
-      let {identifier, path: origPath, reactive} = original.fullPath;
-      let currNode: PropertyPathNode = registry.getOrCreateIdentifier(
-        identifier,
-        reactive,
-      );
+      let {identifier, path: origPath} = original.fullPath;
+      let currNode: PropertyPathNode =
+        registry.getOrCreateIdentifier(identifier);
      for (let i = 0; i < origPath.length; i++) {
        const entry = origPath[i];
        // If the base is known to be non-null, replace with a non-optional load
@@ -682,130 +591,3 @@ function reduceMaybeOptionalChains(
    }
  } while (changed);
 }
-
-function getAssumedInvokedFunctions(
-  fn: HIRFunction,
-  temporaries: Map<
-    IdentifierId,
-    {fn: LoweredFunction; mayInvoke: Set<LoweredFunction>}
-  > = new Map(),
-): ReadonlySet<LoweredFunction> {
-  const hoistableFunctions = new Set<LoweredFunction>();
-  /**
-   * Step 1: Conservatively collect identifier to function expression mappings
-   */
-  for (const block of fn.body.blocks.values()) {
-    for (const {lvalue, value} of block.instructions) {
-      /**
-       * Conservatively only match function expressions which can have guaranteed ssa.
-       * ObjectMethods and ObjectProperties do not.
-       */
-      if (value.kind === 'FunctionExpression') {
-        temporaries.set(lvalue.identifier.id, {
-          fn: value.loweredFunc,
-          mayInvoke: new Set(),
-        });
-      } else if (value.kind === 'StoreLocal') {
-        const lvalue = value.lvalue.place.identifier;
-        const maybeLoweredFunc = temporaries.get(value.value.identifier.id);
-        if (maybeLoweredFunc != null) {
-          temporaries.set(lvalue.id, maybeLoweredFunc);
-        }
-      } else if (value.kind === 'LoadLocal') {
-        const maybeLoweredFunc = temporaries.get(value.place.identifier.id);
-        if (maybeLoweredFunc != null) {
-          temporaries.set(lvalue.identifier.id, maybeLoweredFunc);
-        }
-      }
-    }
-  }
-  /**
-   * Step 2: Forward pass to do analysis of assumed function calls. Note that
-   * this is conservative and does not count indirect references through
-   * containers (e.g. `return {cb: () => {...}})`).
-   */
-  for (const block of fn.body.blocks.values()) {
-    for (const {lvalue, value} of block.instructions) {
-      if (value.kind === 'CallExpression') {
-        const callee = value.callee;
-        const maybeHook = getHookKind(fn.env, callee.identifier);
-        const maybeLoweredFunc = temporaries.get(callee.identifier.id);
-        if (maybeLoweredFunc != null) {
-          // Direct calls
-          hoistableFunctions.add(maybeLoweredFunc.fn);
-        } else if (maybeHook != null) {
-          /**
-           * Assume arguments to all hooks are safe to invoke
-           */
-          for (const arg of value.args) {
-            if (arg.kind === 'Identifier') {
-              const maybeLoweredFunc = temporaries.get(arg.identifier.id);
-              if (maybeLoweredFunc != null) {
-                hoistableFunctions.add(maybeLoweredFunc.fn);
-              }
-            }
-          }
-        }
-      } else if (value.kind === 'JsxExpression') {
-        /**
-         * Assume JSX attributes and children are safe to invoke
-         */
-        for (const attr of value.props) {
-          if (attr.kind === 'JsxSpreadAttribute') {
-            continue;
-          }
-          const maybeLoweredFunc = temporaries.get(attr.place.identifier.id);
-          if (maybeLoweredFunc != null) {
-            hoistableFunctions.add(maybeLoweredFunc.fn);
-          }
-        }
-        for (const child of value.children ?? []) {
-          const maybeLoweredFunc = temporaries.get(child.identifier.id);
-          if (maybeLoweredFunc != null) {
-            hoistableFunctions.add(maybeLoweredFunc.fn);
-          }
-        }
-      } else if (value.kind === 'FunctionExpression') {
-        /**
-         * Recursively traverse into other function expressions which may invoke
-         * or pass already declared functions to react (e.g. as JSXAttributes).
-         *
-         * If lambda A calls lambda B, we assume lambda B is safe to invoke if
-         * lambda A is -- even if lambda B is conditionally called. (see
-         * `conditional-call-chain` fixture for example).
-         */
-        const loweredFunc = value.loweredFunc.func;
-        const lambdasCalled = getAssumedInvokedFunctions(
-          loweredFunc,
-          temporaries,
-        );
-        const maybeLoweredFunc = temporaries.get(lvalue.identifier.id);
-        if (maybeLoweredFunc != null) {
-          for (const called of lambdasCalled) {
-            maybeLoweredFunc.mayInvoke.add(called);
-          }
-        }
-      }
-    }
-    if (block.terminal.kind === 'return') {
-      /**
-       * Assume directly returned functions are safe to call
-       */
-      const maybeLoweredFunc = temporaries.get(
-        block.terminal.value.identifier.id,
-      );
-      if (maybeLoweredFunc != null) {
-        hoistableFunctions.add(maybeLoweredFunc.fn);
-      }
-    }
-  }
-
-  for (const [_, {fn, mayInvoke}] of temporaries) {
-    if (hoistableFunctions.has(fn)) {
-      for (const called of mayInvoke) {
-        hoistableFunctions.add(called);
-      }
-    }
-  }
-  return hoistableFunctions;
-}
--- a/compiler/packages/babel-plugin-react-compiler/src/HIR/CollectOptionalChainDependencies.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/HIR/CollectOptionalChainDependencies.ts
@@ -1,10 +1,3 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
 import {CompilerError} from '..';
 import {assertNonNull} from './CollectHoistablePropertyLoads';
 import {
@@ -186,13 +179,7 @@ function matchOptionalTestBlock(
        reason:
          '[OptionalChainDeps] Inconsistent optional chaining property load',
        description: `Test=${printIdentifier(terminal.test.identifier)} PropertyLoad base=${printIdentifier(propertyLoad.value.object.identifier)}`,
-        details: [
-          {
-            kind: 'error',
-            loc: propertyLoad.loc,
-            message: null,
-          },
-        ],
+        loc: propertyLoad.loc,
      },
    );

@@ -200,14 +187,7 @@ function matchOptionalTestBlock(
      storeLocal.value.identifier.id === propertyLoad.lvalue.identifier.id,
      {
        reason: '[OptionalChainDeps] Unexpected storeLocal',
-        description: null,
-        details: [
-          {
-            kind: 'error',
-            loc: propertyLoad.loc,
-            message: null,
-          },
-        ],
+        loc: propertyLoad.loc,
      },
    );
    if (
@@ -224,14 +204,7 @@ function matchOptionalTestBlock(
        alternate.instructions[1].value.kind === 'StoreLocal',
      {
        reason: 'Unexpected alternate structure',
-        description: null,
-        details: [
-          {
-            kind: 'error',
-            loc: terminal.loc,
-            message: null,
-          },
-        ],
+        loc: terminal.loc,
      },
    );

@@ -267,14 +240,7 @@ function traverseOptionalBlock(
  if (maybeTest.terminal.kind === 'branch') {
    CompilerError.invariant(optional.terminal.optional, {
      reason: '[OptionalChainDeps] Expect base case to be always optional',
-      description: null,
-      details: [
-        {
-          kind: 'error',
-          loc: optional.terminal.loc,
-          message: null,
-        },
-      ],
+      loc: optional.terminal.loc,
    });
    /**
     * Optional base expressions are currently within value blocks which cannot
@@ -312,19 +278,11 @@ function traverseOptionalBlock(
        maybeTest.instructions.at(-1)!.lvalue.identifier.id,
      {
        reason: '[OptionalChainDeps] Unexpected test expression',
-        description: null,
-        details: [
-          {
-            kind: 'error',
-            loc: maybeTest.terminal.loc,
-            message: null,
-          },
-        ],
+        loc: maybeTest.terminal.loc,
      },
    );
    baseObject = {
      identifier: maybeTest.instructions[0].value.place.identifier,
-      reactive: maybeTest.instructions[0].value.place.reactive,
      path,
    };
    test = maybeTest.terminal;
@@ -408,14 +366,7 @@ function traverseOptionalBlock(
      reason:
        '[OptionalChainDeps] Unexpected instructions an inner optional block. ' +
        'This indicates that the compiler may be incorrectly concatenating two unrelated optional chains',
-      description: null,
-      details: [
-        {
-          kind: 'error',
-          loc: optional.terminal.loc,
-          message: null,
-        },
-      ],
+      loc: optional.terminal.loc,
    });
  }
  const matchConsequentResult = matchOptionalTestBlock(test, context.blocks);
@@ -428,18 +379,11 @@ function traverseOptionalBlock(
    {
      reason: '[OptionalChainDeps] Unexpected optional goto-fallthrough',
      description: `${matchConsequentResult.consequentGoto} != ${optional.terminal.fallthrough}`,
-      details: [
-        {
-          kind: 'error',
-          loc: optional.terminal.loc,
-          message: null,
-        },
-      ],
+      loc: optional.terminal.loc,
    },
  );
  const load = {
    identifier: baseObject.identifier,
-    reactive: baseObject.reactive,
    path: [
      ...baseObject.path,
      {
--- a/compiler/packages/babel-plugin-react-compiler/src/HIR/ComputeUnconditionalBlocks.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/HIR/ComputeUnconditionalBlocks.ts
@@ -24,14 +24,7 @@ export function computeUnconditionalBlocks(fn: HIRFunction): Set<BlockId> {
    CompilerError.invariant(!unconditionalBlocks.has(current), {
      reason:
        'Internal error: non-terminating loop in ComputeUnconditionalBlocks',
-      description: null,
-      details: [
-        {
-          kind: 'error',
-          loc: null,
-          message: null,
-        },
-      ],
+      loc: null,
      suggestions: null,
    });
    unconditionalBlocks.add(current);
--- a/compiler/packages/babel-plugin-react-compiler/src/HIR/DefaultModuleTypeProvider.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/HIR/DefaultModuleTypeProvider.ts
@@ -1,109 +0,0 @@
-/**
- * Copyright (c) Meta Platforms, Inc. and affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- */
-
-import {Effect, ValueKind} from '..';
-import {TypeConfig} from './TypeSchema';
-
-/**
- * Libraries developed before we officially documented the [Rules of React](https://react.dev/reference/rules)
- * implement APIs which cannot be memoized safely, either via manual or automatic memoization.
- *
- * Any non-hook API that is designed to be called during render (not events/effects) should be safe to memoize:
- *
- * ```js
- * function Component() {
- *   const {someFunction} = useLibrary();
- *   // it should always be safe to memoize functions like this
- *  const result = useMemo(() => someFunction(), [someFunction]);
- * }
- * ```
- *
- * However, some APIs implement "interior mutability" — mutating values rather than copying into a new value
- * and setting state with the new value. Such functions (`someFunction()` in the example) could return different
- * values even though the function itself is the same object. This breaks memoization, since React relies on
- * the outer object (or function) changing if part of its value has changed.
- *
- * Given that we didn't have the Rules of React precisely documented prior to the introduction of React compiler,
- * it's understandable that some libraries accidentally shipped APIs that break this rule. However, developers
- * can easily run into pitfalls with these APIs. They may manually memoize them, which can break their app. Or
- * they may try using React Compiler, and think that the compiler has broken their code.
- *
- * To help ensure that developers can successfully use the compiler with existing code, this file teaches the
- * compiler about specific APIs that are known to be incompatible with memoization. We've tried to be as precise
- * as possible.
- *
- * The React team is open to collaborating with library authors to help develop compatible versions of these APIs,
- * and we have already reached out to the teams who own any API listed here to ensure they are aware of the issue.
- */
-export function defaultModuleTypeProvider(
-  moduleName: string,
-): TypeConfig | null {
-  switch (moduleName) {
-    case 'react-hook-form': {
-      return {
-        kind: 'object',
-        properties: {
-          useForm: {
-            kind: 'hook',
-            returnType: {
-              kind: 'object',
-              properties: {
-                // Only the `watch()` function returned by react-hook-form's `useForm()` API is incompatible
-                watch: {
-                  kind: 'function',
-                  positionalParams: [],
-                  restParam: Effect.Read,
-                  calleeEffect: Effect.Read,
-                  returnType: {kind: 'type', name: 'Any'},
-                  returnValueKind: ValueKind.Mutable,
-                  knownIncompatible: `React Hook Form's \`useForm()\` API returns a \`watch()\` function which cannot be memoized safely.`,
-                },
-              },
-            },
-          },
-        },
-      };
-    }
-    case '@tanstack/react-table': {
-      return {
-        kind: 'object',
-        properties: {
-          /*
-           * Many of the properties of `useReactTable()`'s return value are incompatible, so we mark the entire hook
-           * as incompatible
-           */
-          useReactTable: {
-            kind: 'hook',
-            positionalParams: [],
-            restParam: Effect.Read,
-            returnType: {kind: 'type', name: 'Any'},
-            knownIncompatible: `TanStack Table's \`useReactTable()\` API returns functions that cannot be memoized safely`,
-          },
-        },
-      };
-    }
-    case '@tanstack/react-virtual': {
-      return {
-        kind: 'object',
-        properties: {
-          /*
-           * Many of the properties of `useVirtualizer()`'s return value are incompatible, so we mark the entire hook
-           * as incompatible
-           */
-          useVirtualizer: {
-            kind: 'hook',
-            positionalParams: [],
-            restParam: Effect.Read,
-            returnType: {kind: 'type', name: 'Any'},
-            knownIncompatible: `TanStack Virtual's \`useVirtualizer()\` API returns functions that cannot be memoized safely`,
-          },
-        },
-      };
-    }
-  }
-  return null;
-}
--- a/compiler/packages/babel-plugin-react-compiler/src/HIR/DeriveMinimalDependenciesHIR.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/HIR/DeriveMinimalDependenciesHIR.ts
@@ -25,9 +25,8 @@ export class ReactiveScopeDependencyTreeHIR {
   * `identifier.path`, or `identifier?.path` is in this map, it is safe to
   * evaluate (non-optional) PropertyLoads from.
   */
-  #hoistableObjects: Map<Identifier, HoistableNode & {reactive: boolean}> =
-    new Map();
-  #deps: Map<Identifier, DependencyNode & {reactive: boolean}> = new Map();
+  #hoistableObjects: Map<Identifier, HoistableNode> = new Map();
+  #deps: Map<Identifier, DependencyNode> = new Map();

  /**
   * @param hoistableObjects a set of paths from which we can safely evaluate
@@ -36,10 +35,9 @@ export class ReactiveScopeDependencyTreeHIR {
   * duplicates when traversing the CFG.
   */
  constructor(hoistableObjects: Iterable<ReactiveScopeDependency>) {
-    for (const {path, identifier, reactive} of hoistableObjects) {
+    for (const {path, identifier} of hoistableObjects) {
      let currNode = ReactiveScopeDependencyTreeHIR.#getOrCreateRoot(
        identifier,
-        reactive,
        this.#hoistableObjects,
        path.length > 0 && path[0].optional ? 'Optional' : 'NonNull',
      );
@@ -54,14 +52,7 @@ export class ReactiveScopeDependencyTreeHIR {
          prevAccessType == null || prevAccessType === accessType,
          {
            reason: 'Conflicting access types',
-            description: null,
-            details: [
-              {
-                kind: 'error',
-                loc: GeneratedSource,
-                message: null,
-              },
-            ],
+            loc: GeneratedSource,
          },
        );
        let nextNode = currNode.properties.get(path[i].property);
@@ -79,8 +70,7 @@ export class ReactiveScopeDependencyTreeHIR {

  static #getOrCreateRoot<T extends string>(
    identifier: Identifier,
-    reactive: boolean,
-    roots: Map<Identifier, TreeNode<T> & {reactive: boolean}>,
+    roots: Map<Identifier, TreeNode<T>>,
    defaultAccessType: T,
  ): TreeNode<T> {
    // roots can always be accessed unconditionally in JS
@@ -89,22 +79,9 @@ export class ReactiveScopeDependencyTreeHIR {
    if (rootNode === undefined) {
      rootNode = {
        properties: new Map(),
-        reactive,
        accessType: defaultAccessType,
      };
      roots.set(identifier, rootNode);
-    } else {
-      CompilerError.invariant(reactive === rootNode.reactive, {
-        reason: '[DeriveMinimalDependenciesHIR] Conflicting reactive root flag',
-        description: `Identifier ${printIdentifier(identifier)}`,
-        details: [
-          {
-            kind: 'error',
-            loc: GeneratedSource,
-            message: null,
-          },
-        ],
-      });
    }
    return rootNode;
  }
@@ -115,10 +92,9 @@ export class ReactiveScopeDependencyTreeHIR {
   * safe-to-evaluate subpath
   */
  addDependency(dep: ReactiveScopeDependency): void {
-    const {identifier, reactive, path} = dep;
+    const {identifier, path} = dep;
    let depCursor = ReactiveScopeDependencyTreeHIR.#getOrCreateRoot(
      identifier,
-      reactive,
      this.#deps,
      PropertyAccessType.UnconditionalAccess,
    );
@@ -196,13 +172,7 @@ export class ReactiveScopeDependencyTreeHIR {
  deriveMinimalDependencies(): Set<ReactiveScopeDependency> {
    const results = new Set<ReactiveScopeDependency>();
    for (const [rootId, rootNode] of this.#deps.entries()) {
-      collectMinimalDependenciesInSubtree(
-        rootNode,
-        rootNode.reactive,
-        rootId,
-        [],
-        results,
-      );
+      collectMinimalDependenciesInSubtree(rootNode, rootId, [], results);
    }

    return results;
@@ -324,24 +294,25 @@ type HoistableNode = TreeNode<'Optional' | 'NonNull'>;
 type DependencyNode = TreeNode<PropertyAccessType>;

 /**
+ * TODO: this is directly pasted from DeriveMinimalDependencies. Since we no
+ * longer have conditionally accessed nodes, we can simplify
+ *
 * Recursively calculates minimal dependencies in a subtree.
 * @param node DependencyNode representing a dependency subtree.
 * @returns a minimal list of dependencies in this subtree.
 */
 function collectMinimalDependenciesInSubtree(
  node: DependencyNode,
-  reactive: boolean,
  rootIdentifier: Identifier,
  path: Array<DependencyPathEntry>,
  results: Set<ReactiveScopeDependency>,
 ): void {
  if (isDependency(node.accessType)) {
-    results.add({identifier: rootIdentifier, reactive, path});
+    results.add({identifier: rootIdentifier, path});
  } else {
    for (const [childName, childNode] of node.properties) {
      collectMinimalDependenciesInSubtree(
        childNode,
-        reactive,
        rootIdentifier,
        [
          ...path,
--- a/compiler/packages/babel-plugin-react-compiler/src/HIR/Dominator.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/HIR/Dominator.ts
@@ -89,13 +89,7 @@ export class Dominator<T> {
    CompilerError.invariant(dominator !== undefined, {
      reason: 'Unknown node',
      description: null,
-      details: [
-        {
-          kind: 'error',
-          loc: null,
-          message: null,
-        },
-      ],
+      loc: null,
      suggestions: null,
    });
    return dominator === id ? null : dominator;
@@ -136,13 +130,7 @@ export class PostDominator<T> {
    CompilerError.invariant(dominator !== undefined, {
      reason: 'Unknown node',
      description: null,
-      details: [
-        {
-          kind: 'error',
-          loc: null,
-          message: null,
-        },
-      ],
+      loc: null,
      suggestions: null,
    });
    return dominator === id ? null : dominator;
@@ -187,13 +175,7 @@ function computeImmediateDominators<T>(graph: Graph<T>): Map<T, T> {
      CompilerError.invariant(newIdom !== null, {
        reason: `At least one predecessor must have been visited for block ${id}`,
        description: null,
-        details: [
-          {
-            kind: 'error',
-            loc: null,
-            message: null,
-          },
-        ],
+        loc: null,
        suggestions: null,
      });

--- a/compiler/packages/babel-plugin-react-compiler/src/HIR/Environment.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/HIR/Environment.ts
@@ -9,7 +9,13 @@ import * as t from '@babel/types';
 import {ZodError, z} from 'zod';
 import {fromZodError} from 'zod-validation-error';
 import {CompilerError} from '../CompilerError';
-import {Logger, ProgramContext} from '../Entrypoint';
+import {
+  CompilationMode,
+  Logger,
+  PanicThresholdOptions,
+  parsePluginOptions,
+  PluginOptions,
+} from '../Entrypoint';
 import {Err, Ok, Result} from '../Utils/Result';
 import {
  DEFAULT_GLOBALS,
@@ -47,10 +53,8 @@ import {
  ShapeRegistry,
  addHook,
 } from './ObjectShape';
-import {Scope as BabelScope, NodePath} from '@babel/traverse';
+import {Scope as BabelScope} from '@babel/traverse';
 import {TypeSchema} from './TypeSchema';
-import {FlowTypeEnv} from '../Flood/Types';
-import {defaultModuleTypeProvider} from './DefaultModuleTypeProvider';

 export const ReactElementSymbolSchema = z.object({
  elementSymbol: z.union([
@@ -80,8 +84,6 @@ export const InstrumentationSchema = z
  );

 export type ExternalFunction = z.infer<typeof ExternalFunctionSchema>;
-export const USE_FIRE_FUNCTION_NAME = 'useFire';
-export const EMIT_FREEZE_GLOBAL_GATING = '__DEV__';

 export const MacroMethodSchema = z.union([
  z.object({type: z.literal('wildcard')}),
@@ -94,8 +96,6 @@ export const MacroSchema = z.union([
  z.tuple([z.string(), z.array(MacroMethodSchema)]),
 ]);

-export type CompilerMode = 'all_features' | 'no_inferred_memo';
-
 export type Macro = z.infer<typeof MacroSchema>;
 export type MacroMethod = z.infer<typeof MacroMethodSchema>;

@@ -152,7 +152,7 @@ export type Hook = z.infer<typeof HookSchema>;
 *   missing some recursive Object / Function shapeIds
 */

-export const EnvironmentConfigSchema = z.object({
+const EnvironmentConfigSchema = z.object({
  customHooks: z.map(z.string(), HookSchema).default(new Map()),

  /**
@@ -245,12 +245,6 @@ export const EnvironmentConfigSchema = z.object({
   */
  enableUseTypeAnnotations: z.boolean().default(false),

-  /**
-   * Allows specifying a function that can populate HIR with type information from
-   * Flow
-   */
-  flowTypeProvider: z.nullable(z.function().args(z.string())).default(null),
-
  /**
   * Enables inference of optional dependency chains. Without this flag
   * a property chain such as `props?.items?.foo` will infer as a dep on
@@ -261,8 +255,6 @@ export const EnvironmentConfigSchema = z.object({

  enableFire: z.boolean().default(false),

-  enableNameAnonymousFunctions: z.boolean().default(false),
-
  /**
   * Enables inference and auto-insertion of effect dependencies. Takes in an array of
   * configurable module and import pairs to allow for user-land experimentation. For example,
@@ -270,19 +262,21 @@ export const EnvironmentConfigSchema = z.object({
   *   {
   *     module: 'react',
   *     imported: 'useEffect',
-   *     autodepsIndex: 1,
+   *     numRequiredArgs: 1,
   *   },{
   *     module: 'MyExperimentalEffectHooks',
   *     imported: 'useExperimentalEffect',
-   *     autodepsIndex: 2,
+   *     numRequiredArgs: 2,
   *   },
   * ]
   * would insert dependencies for calls of `useEffect` imported from `react` and calls of
   * useExperimentalEffect` from `MyExperimentalEffectHooks`.
   *
-   * `autodepsIndex` tells the compiler which index we expect the AUTODEPS to appear in.
-   *  With the configuration above, we'd insert dependencies for `useEffect` if it has two
-   *  arguments, and the second is AUTODEPS.
+   * `numRequiredArgs` tells the compiler the amount of arguments required to append a dependency
+   *  array to the end of the call. With the configuration above, we'd insert dependencies for
+   *  `useEffect` if it is only given a single argument and it would be appended to the argument list.
+   *
+   * numRequiredArgs must always be greater than 0, otherwise there is no function to analyze for dependencies
   *
   * Still experimental.
   */
@@ -291,7 +285,7 @@ export const EnvironmentConfigSchema = z.object({
      z.array(
        z.object({
          function: ExternalFunctionSchema,
-          autodepsIndex: z.number().min(1, 'autodepsIndex must be > 0'),
+          numRequiredArgs: z.number().min(1, 'numRequiredArgs must be > 0'),
        }),
      ),
    )
@@ -323,16 +317,10 @@ export const EnvironmentConfigSchema = z.object({
  validateNoSetStateInRender: z.boolean().default(true),

  /**
-   * Validates that setState is not called synchronously within an effect (useEffect and friends).
+   * Validates that setState is not called directly within a passive effect (useEffect).
   * Scheduling a setState (with an event listener, subscription, etc) is valid.
   */
-  validateNoSetStateInEffects: z.boolean().default(false),
-
-  /**
-   * Validates that effects are not used to calculate derived data which could instead be computed
-   * during render.
-   */
-  validateNoDerivedComputationsInEffects: z.boolean().default(false),
+  validateNoSetStateInPassiveEffects: z.boolean().default(false),

  /**
   * Validates against creating JSX within a try block and recommends using an error boundary
@@ -340,11 +328,6 @@ export const EnvironmentConfigSchema = z.object({
   */
  validateNoJSXInTryStatements: z.boolean().default(false),

-  /**
-   * Validates against dynamically creating components during render.
-   */
-  validateStaticComponents: z.boolean().default(false),
-
  /**
   * Validates that the dependencies of all effect hooks are memoized. This helps ensure
   * that Forget does not introduce infinite renders caused by a dependency changing,
@@ -373,11 +356,6 @@ export const EnvironmentConfigSchema = z.object({
   */
  validateNoImpureFunctionsInRender: z.boolean().default(false),

-  /**
-   * Validate against passing mutable functions to hooks
-   */
-  validateNoFreezingKnownMutableFunctions: z.boolean().default(false),
-
  /*
   * When enabled, the compiler assumes that hooks follow the Rules of React:
   * - Hooks may memoize computation based on any of their parameters, thus
@@ -572,6 +550,8 @@ export const EnvironmentConfigSchema = z.object({
   */
  disableMemoizationForDebugging: z.boolean().default(false),

+  enableMinimalTransformsForRetry: z.boolean().default(false),
+
  /**
   * When true, rather using memoized values, the compiler will always re-compute
   * values, and then use a heuristic to compare the memoized value to the newly
@@ -619,14 +599,7 @@ export const EnvironmentConfigSchema = z.object({
   *
   * Here the variables `ref` and `myRef` will be typed as Refs.
   */
-  enableTreatRefLikeIdentifiersAsRefs: z.boolean().default(true),
-
-  /**
-   * Treat identifiers as SetState type if both
-   * - they are named with a "set-" prefix
-   * - they are called somewhere
-   */
-  enableTreatSetIdentifiersAsStateSetters: z.boolean().default(false),
+  enableTreatRefLikeIdentifiersAsRefs: z.boolean().default(false),

  /*
   * If specified a value, the compiler lowers any calls to `useContext` to use
@@ -649,35 +622,200 @@ export const EnvironmentConfigSchema = z.object({
   * ```
   */
  lowerContextAccess: ExternalFunctionSchema.nullable().default(null),
-
-  /**
-   * If enabled, will validate useMemos that don't return any values:
-   *
-   * Valid:
-   *   useMemo(() => foo, [foo]);
-   *   useMemo(() => { return foo }, [foo]);
-   * Invalid:
-   *   useMemo(() => { ... }, [...]);
-   */
-  validateNoVoidUseMemo: z.boolean().default(false),
-
-  /**
-   * Validates that Components/Hooks are always defined at module level. This prevents scope
-   * reference errors that occur when the compiler attempts to optimize the nested component/hook
-   * while its parent function remains uncompiled.
-   */
-  validateNoDynamicallyCreatedComponentsOrHooks: z.boolean().default(false),
-
-  /**
-   * When enabled, allows setState calls in effects when the value being set is
-   * derived from a ref. This is useful for patterns where initial layout measurements
-   * from refs need to be stored in state during mount.
-   */
-  enableAllowSetStateFromRefsInEffects: z.boolean().default(true),
 });

 export type EnvironmentConfig = z.infer<typeof EnvironmentConfigSchema>;

+export const MINIMAL_RETRY_CONFIG: PartialEnvironmentConfig = {
+  validateHooksUsage: false,
+  validateRefAccessDuringRender: false,
+  validateNoSetStateInRender: false,
+  validateNoSetStateInPassiveEffects: false,
+  validateNoJSXInTryStatements: false,
+  validateMemoizedEffectDependencies: false,
+  validateNoCapitalizedCalls: null,
+  validateBlocklistedImports: null,
+  enableMinimalTransformsForRetry: true,
+};
+/**
+ * For test fixtures and playground only.
+ *
+ * Pragmas are straightforward to parse for boolean options (`:true` and
+ * `:false`). These are 'enabled' config values for non-boolean configs (i.e.
+ * what is used when parsing `:true`).
+ */
+const testComplexConfigDefaults: PartialEnvironmentConfig = {
+  validateNoCapitalizedCalls: [],
+  enableChangeDetectionForDebugging: {
+    source: 'react-compiler-runtime',
+    importSpecifierName: '$structuralCheck',
+  },
+  enableEmitFreeze: {
+    source: 'react-compiler-runtime',
+    importSpecifierName: 'makeReadOnly',
+  },
+  enableEmitInstrumentForget: {
+    fn: {
+      source: 'react-compiler-runtime',
+      importSpecifierName: 'useRenderCounter',
+    },
+    gating: {
+      source: 'react-compiler-runtime',
+      importSpecifierName: 'shouldInstrument',
+    },
+    globalGating: '__DEV__',
+  },
+  enableEmitHookGuards: {
+    source: 'react-compiler-runtime',
+    importSpecifierName: '$dispatcherGuard',
+  },
+  inlineJsxTransform: {
+    elementSymbol: 'react.transitional.element',
+    globalDevVar: 'DEV',
+  },
+  lowerContextAccess: {
+    source: 'react-compiler-runtime',
+    importSpecifierName: 'useContext_withSelector',
+  },
+  inferEffectDependencies: [
+    {
+      function: {
+        source: 'react',
+        importSpecifierName: 'useEffect',
+      },
+      numRequiredArgs: 1,
+    },
+    {
+      function: {
+        source: 'shared-runtime',
+        importSpecifierName: 'useSpecialEffect',
+      },
+      numRequiredArgs: 2,
+    },
+    {
+      function: {
+        source: 'useEffectWrapper',
+        importSpecifierName: 'default',
+      },
+      numRequiredArgs: 1,
+    },
+  ],
+};
+
+/**
+ * For snap test fixtures and playground only.
+ */
+function parseConfigPragmaEnvironmentForTest(
+  pragma: string,
+): EnvironmentConfig {
+  const maybeConfig: any = {};
+  // Get the defaults to programmatically check for boolean properties
+  const defaultConfig = EnvironmentConfigSchema.parse({});
+
+  for (const token of pragma.split(' ')) {
+    if (!token.startsWith('@')) {
+      continue;
+    }
+    const keyVal = token.slice(1);
+    let [key, val = undefined] = keyVal.split(':');
+    const isSet = val === undefined || val === 'true';
+
+    if (isSet && key in testComplexConfigDefaults) {
+      maybeConfig[key] =
+        testComplexConfigDefaults[key as keyof PartialEnvironmentConfig];
+      continue;
+    }
+
+    if (key === 'customMacros' && val) {
+      const valSplit = val.split('.');
+      if (valSplit.length > 0) {
+        const props = [];
+        for (const elt of valSplit.slice(1)) {
+          if (elt === '*') {
+            props.push({type: 'wildcard'});
+          } else if (elt.length > 0) {
+            props.push({type: 'name', name: elt});
+          }
+        }
+        maybeConfig[key] = [[valSplit[0], props]];
+      }
+      continue;
+    }
+
+    if (
+      key !== 'enableResetCacheOnSourceFileChanges' &&
+      typeof defaultConfig[key as keyof EnvironmentConfig] !== 'boolean'
+    ) {
+      // skip parsing non-boolean properties
+      continue;
+    }
+    if (val === undefined || val === 'true') {
+      maybeConfig[key] = true;
+    } else {
+      maybeConfig[key] = false;
+    }
+  }
+  const config = EnvironmentConfigSchema.safeParse(maybeConfig);
+  if (config.success) {
+    /**
+     * Unless explicitly enabled, do not insert HMR handling code
+     * in test fixtures or playground to reduce visual noise.
+     */
+    if (config.data.enableResetCacheOnSourceFileChanges == null) {
+      config.data.enableResetCacheOnSourceFileChanges = false;
+    }
+    return config.data;
+  }
+  CompilerError.invariant(false, {
+    reason: 'Internal error, could not parse config from pragma string',
+    description: `${fromZodError(config.error)}`,
+    loc: null,
+    suggestions: null,
+  });
+}
+export function parseConfigPragmaForTests(
+  pragma: string,
+  defaults: {
+    compilationMode: CompilationMode;
+  },
+): PluginOptions {
+  const environment = parseConfigPragmaEnvironmentForTest(pragma);
+  let compilationMode: CompilationMode = defaults.compilationMode;
+  let panicThreshold: PanicThresholdOptions = 'all_errors';
+  for (const token of pragma.split(' ')) {
+    if (!token.startsWith('@')) {
+      continue;
+    }
+    switch (token) {
+      case '@compilationMode(annotation)': {
+        compilationMode = 'annotation';
+        break;
+      }
+      case '@compilationMode(infer)': {
+        compilationMode = 'infer';
+        break;
+      }
+      case '@compilationMode(all)': {
+        compilationMode = 'all';
+        break;
+      }
+      case '@compilationMode(syntax)': {
+        compilationMode = 'syntax';
+        break;
+      }
+      case '@panicThreshold(none)': {
+        panicThreshold = 'none';
+        break;
+      }
+    }
+  }
+  return parsePluginOptions({
+    environment,
+    compilationMode,
+    panicThreshold,
+  });
+}
+
 export type PartialEnvironmentConfig = Partial<EnvironmentConfig>;

 export type ReactFunctionType = 'Component' | 'Hook' | 'Other';
@@ -713,42 +851,34 @@ export class Environment {
  code: string | null;
  config: EnvironmentConfig;
  fnType: ReactFunctionType;
-  compilerMode: CompilerMode;
-  programContext: ProgramContext;
+  useMemoCacheIdentifier: string;
+  hasLoweredContextAccess: boolean;
  hasFireRewrite: boolean;
-  hasInferredEffect: boolean;
-  inferredEffectLocations: Set<SourceLocation> = new Set();

  #contextIdentifiers: Set<t.Identifier>;
  #hoistedIdentifiers: Set<t.Identifier>;
-  parentFunction: NodePath<t.Function>;
-
-  #flowTypeEnvironment: FlowTypeEnv | null;

  constructor(
    scope: BabelScope,
    fnType: ReactFunctionType,
-    compilerMode: CompilerMode,
    config: EnvironmentConfig,
    contextIdentifiers: Set<t.Identifier>,
-    parentFunction: NodePath<t.Function>, // the outermost function being compiled
    logger: Logger | null,
    filename: string | null,
    code: string | null,
-    programContext: ProgramContext,
+    useMemoCacheIdentifier: string,
  ) {
    this.#scope = scope;
    this.fnType = fnType;
-    this.compilerMode = compilerMode;
    this.config = config;
    this.filename = filename;
    this.code = code;
    this.logger = logger;
-    this.programContext = programContext;
+    this.useMemoCacheIdentifier = useMemoCacheIdentifier;
    this.#shapes = new Map(DEFAULT_SHAPES);
    this.#globals = new Map(DEFAULT_GLOBALS);
+    this.hasLoweredContextAccess = false;
    this.hasFireRewrite = false;
-    this.hasInferredEffect = false;

    if (
      config.disableMemoizationForDebugging &&
@@ -766,13 +896,7 @@ export class Environment {
      CompilerError.invariant(!this.#globals.has(hookName), {
        reason: `[Globals] Found existing definition in global registry for custom hook ${hookName}`,
        description: null,
-        details: [
-          {
-            kind: 'error',
-            loc: null,
-            message: null,
-          },
-        ],
+        loc: null,
        suggestions: null,
      });
      this.#globals.set(
@@ -796,47 +920,8 @@ export class Environment {
      this.#moduleTypes.set(REANIMATED_MODULE_NAME, reanimatedModuleType);
    }

-    this.parentFunction = parentFunction;
    this.#contextIdentifiers = contextIdentifiers;
    this.#hoistedIdentifiers = new Set();
-
-    if (config.flowTypeProvider != null) {
-      this.#flowTypeEnvironment = new FlowTypeEnv();
-      CompilerError.invariant(code != null, {
-        reason:
-          'Expected Environment to be initialized with source code when a Flow type provider is specified',
-        description: null,
-        details: [
-          {
-            kind: 'error',
-            loc: null,
-            message: null,
-          },
-        ],
-      });
-      this.#flowTypeEnvironment.init(this, code);
-    } else {
-      this.#flowTypeEnvironment = null;
-    }
-  }
-
-  get typeContext(): FlowTypeEnv {
-    CompilerError.invariant(this.#flowTypeEnvironment != null, {
-      reason: 'Flow type environment not initialized',
-      description: null,
-      details: [
-        {
-          kind: 'error',
-          loc: null,
-          message: null,
-        },
-      ],
-    });
-    return this.#flowTypeEnvironment;
-  }
-
-  get isInferredMemoEnabled(): boolean {
-    return this.compilerMode !== 'no_inferred_memo';
  }

  get nextIdentifierId(): IdentifierId {
@@ -851,23 +936,6 @@ export class Environment {
    return makeScopeId(this.#nextScope++);
  }

-  get scope(): BabelScope {
-    return this.#scope;
-  }
-
-  logErrors(errors: Result<void, CompilerError>): void {
-    if (errors.isOk() || this.logger == null) {
-      return;
-    }
-    for (const error of errors.unwrapErr().details) {
-      this.logger.logEvent(this.filename, {
-        kind: 'CompileError',
-        detail: error,
-        fnLoc: null,
-      });
-    }
-  }
-
  isContextIdentifier(node: t.Identifier): boolean {
    return this.#contextIdentifiers.has(node);
  }
@@ -897,16 +965,10 @@ export class Environment {
  #resolveModuleType(moduleName: string, loc: SourceLocation): Global | null {
    let moduleType = this.#moduleTypes.get(moduleName);
    if (moduleType === undefined) {
-      /*
-       * NOTE: Zod doesn't work when specifying a function as a default, so we have to
-       * fallback to the default value here
-       */
-      const moduleTypeProvider =
-        this.config.moduleTypeProvider ?? defaultModuleTypeProvider;
-      if (moduleTypeProvider == null) {
+      if (this.config.moduleTypeProvider == null) {
        return null;
      }
-      const unparsedModuleConfig = moduleTypeProvider(moduleName);
+      const unparsedModuleConfig = this.config.moduleTypeProvider(moduleName);
      if (unparsedModuleConfig != null) {
        const parsedModuleConfig = TypeSchema.safeParse(unparsedModuleConfig);
        if (!parsedModuleConfig.success) {
@@ -1063,40 +1125,10 @@ export class Environment {
      moduleName.toLowerCase() === 'react-dom'
    );
  }
-  static knownReactModules: ReadonlyArray<string> = ['react', 'react-dom'];
-
-  getFallthroughPropertyType(
-    receiver: Type,
-    _property: Type,
-  ): BuiltInType | PolyType | null {
-    let shapeId = null;
-    if (receiver.kind === 'Object' || receiver.kind === 'Function') {
-      shapeId = receiver.shapeId;
-    }
-
-    if (shapeId !== null) {
-      const shape = this.#shapes.get(shapeId);
-
-      CompilerError.invariant(shape !== undefined, {
-        reason: `[HIR] Forget internal error: cannot resolve shape ${shapeId}`,
-        description: null,
-        details: [
-          {
-            kind: 'error',
-            loc: null,
-            message: null,
-          },
-        ],
-        suggestions: null,
-      });
-      return shape.properties.get('*') ?? null;
-    }
-    return null;
-  }

  getPropertyType(
    receiver: Type,
-    property: string | number,
+    property: string,
  ): BuiltInType | PolyType | null {
    let shapeId = null;
    if (receiver.kind === 'Object' || receiver.kind === 'Function') {
@@ -1111,28 +1143,20 @@ export class Environment {
      CompilerError.invariant(shape !== undefined, {
        reason: `[HIR] Forget internal error: cannot resolve shape ${shapeId}`,
        description: null,
-        details: [
-          {
-            kind: 'error',
-            loc: null,
-            message: null,
-          },
-        ],
+        loc: null,
        suggestions: null,
      });
-      if (typeof property === 'string') {
-        return (
-          shape.properties.get(property) ??
-          shape.properties.get('*') ??
-          (isHookName(property) ? this.#getCustomHookType() : null)
-        );
-      } else {
-        return shape.properties.get('*') ?? null;
+      let value =
+        shape.properties.get(property) ?? shape.properties.get('*') ?? null;
+      if (value === null && isHookName(property)) {
+        value = this.#getCustomHookType();
      }
-    } else if (typeof property === 'string' && isHookName(property)) {
+      return value;
+    } else if (isHookName(property)) {
      return this.#getCustomHookType();
+    } else {
+      return null;
    }
-    return null;
  }

  getFunctionSignature(type: FunctionType): FunctionSignature | null {
@@ -1142,13 +1166,7 @@ export class Environment {
      CompilerError.invariant(shape !== undefined, {
        reason: `[HIR] Forget internal error: cannot resolve shape ${shapeId}`,
        description: null,
-        details: [
-          {
-            kind: 'error',
-            loc: null,
-            message: null,
-          },
-        ],
+        loc: null,
        suggestions: null,
      });
      return shape.functionType;
--- a/compiler/packages/babel-plugin-react-compiler/src/HIR/FindContextIdentifiers.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/HIR/FindContextIdentifiers.ts
@@ -184,13 +184,7 @@ function handleAssignment(
          CompilerError.invariant(valuePath.isLVal(), {
            reason: `[FindContextIdentifiers] Expected object property value to be an LVal, got: ${valuePath.type}`,
            description: null,
-            details: [
-              {
-                kind: 'error',
-                loc: valuePath.node.loc ?? GeneratedSource,
-                message: null,
-              },
-            ],
+            loc: valuePath.node.loc ?? GeneratedSource,
            suggestions: null,
          });
          handleAssignment(currentFn, identifiers, valuePath);
@@ -198,13 +192,7 @@ function handleAssignment(
          CompilerError.invariant(property.isRestElement(), {
            reason: `[FindContextIdentifiers] Invalid assumptions for babel types.`,
            description: null,
-            details: [
-              {
-                kind: 'error',
-                loc: property.node.loc ?? GeneratedSource,
-                message: null,
-              },
-            ],
+            loc: property.node.loc ?? GeneratedSource,
            suggestions: null,
          });
          handleAssignment(currentFn, identifiers, property);
--- a/compiler/packages/babel-plugin-react-compiler/src/HIR/Globals.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/HIR/Globals.ts
@@ -9,16 +9,10 @@ import {Effect, ValueKind, ValueReason} from './HIR';
 import {
  BUILTIN_SHAPES,
  BuiltInArrayId,
-  BuiltInAutodepsId,
-  BuiltInFireFunctionId,
  BuiltInFireId,
-  BuiltInMapId,
  BuiltInMixedReadonlyId,
-  BuiltInObjectId,
-  BuiltInSetId,
  BuiltInUseActionStateId,
  BuiltInUseContextHookId,
-  BuiltInUseEffectEventId,
  BuiltInUseEffectHookId,
  BuiltInUseInsertionEffectHookId,
  BuiltInUseLayoutEffectHookId,
@@ -27,10 +21,6 @@ import {
  BuiltInUseRefId,
  BuiltInUseStateId,
  BuiltInUseTransitionId,
-  BuiltInWeakMapId,
-  BuiltInWeakSetId,
-  BuiltinEffectEventId,
-  ReanimatedSharedValueId,
  ShapeRegistry,
  addFunction,
  addHook,
@@ -55,23 +45,29 @@ export const DEFAULT_SHAPES: ShapeRegistry = new Map(BUILTIN_SHAPES);

 // Hack until we add ObjectShapes for all globals
 const UNTYPED_GLOBALS: Set<string> = new Set([
+  'String',
  'Object',
  'Function',
+  'Number',
  'RegExp',
  'Date',
  'Error',
+  'Function',
  'TypeError',
  'RangeError',
  'ReferenceError',
  'SyntaxError',
  'URIError',
  'EvalError',
+  'Boolean',
  'DataView',
  'Float32Array',
  'Float64Array',
  'Int8Array',
  'Int16Array',
  'Int32Array',
+  'Map',
+  'Set',
  'WeakMap',
  'Uint8Array',
  'Uint8ClampedArray',
@@ -79,8 +75,16 @@ const UNTYPED_GLOBALS: Set<string> = new Set([
  'Uint32Array',
  'ArrayBuffer',
  'JSON',
+  'parseFloat',
+  'parseInt',
  'console',
+  'isNaN',
  'eval',
+  'isFinite',
+  'encodeURI',
+  'decodeURI',
+  'encodeURIComponent',
+  'decodeURIComponent',
 ]);

 const TYPED_GLOBALS: Array<[string, BuiltInType]> = [
@@ -97,116 +101,6 @@ const TYPED_GLOBALS: Array<[string, BuiltInType]> = [
          returnValueKind: ValueKind.Mutable,
        }),
      ],
-      [
-        /**
-         * Object.fromEntries(iterable)
-         * iterable: An iterable, such as an Array or Map, containing a list of
-         *           objects. Each object should have two properties.
-         * Returns a new object whose properties are given by the entries of the
-         * iterable.
-         */
-        'fromEntries',
-        addFunction(DEFAULT_SHAPES, [], {
-          positionalParams: [Effect.ConditionallyMutate],
-          restParam: null,
-          returnType: {kind: 'Object', shapeId: BuiltInObjectId},
-          calleeEffect: Effect.Read,
-          returnValueKind: ValueKind.Mutable,
-        }),
-      ],
-      [
-        'entries',
-        addFunction(DEFAULT_SHAPES, [], {
-          positionalParams: [Effect.Capture],
-          restParam: null,
-          returnType: {kind: 'Object', shapeId: BuiltInArrayId},
-          calleeEffect: Effect.Read,
-          returnValueKind: ValueKind.Mutable,
-          aliasing: {
-            receiver: '@receiver',
-            params: ['@object'],
-            rest: null,
-            returns: '@returns',
-            temporaries: [],
-            effects: [
-              {
-                kind: 'Create',
-                into: '@returns',
-                reason: ValueReason.KnownReturnSignature,
-                value: ValueKind.Mutable,
-              },
-              // Object values are captured into the return
-              {
-                kind: 'Capture',
-                from: '@object',
-                into: '@returns',
-              },
-            ],
-          },
-        }),
-      ],
-      [
-        'keys',
-        addFunction(DEFAULT_SHAPES, [], {
-          positionalParams: [Effect.Read],
-          restParam: null,
-          returnType: {kind: 'Object', shapeId: BuiltInArrayId},
-          calleeEffect: Effect.Read,
-          returnValueKind: ValueKind.Mutable,
-          aliasing: {
-            receiver: '@receiver',
-            params: ['@object'],
-            rest: null,
-            returns: '@returns',
-            temporaries: [],
-            effects: [
-              {
-                kind: 'Create',
-                into: '@returns',
-                reason: ValueReason.KnownReturnSignature,
-                value: ValueKind.Mutable,
-              },
-              // Only keys are captured, and keys are immutable
-              {
-                kind: 'ImmutableCapture',
-                from: '@object',
-                into: '@returns',
-              },
-            ],
-          },
-        }),
-      ],
-      [
-        'values',
-        addFunction(DEFAULT_SHAPES, [], {
-          positionalParams: [Effect.Capture],
-          restParam: null,
-          returnType: {kind: 'Object', shapeId: BuiltInArrayId},
-          calleeEffect: Effect.Read,
-          returnValueKind: ValueKind.Mutable,
-          aliasing: {
-            receiver: '@receiver',
-            params: ['@object'],
-            rest: null,
-            returns: '@returns',
-            temporaries: [],
-            effects: [
-              {
-                kind: 'Create',
-                into: '@returns',
-                reason: ValueReason.KnownReturnSignature,
-                value: ValueKind.Mutable,
-              },
-              // Object values are captured into the return
-              {
-                kind: 'Capture',
-                from: '@object',
-                into: '@returns',
-              },
-            ],
-          },
-        }),
-      ],
    ]),
  ],
  [
@@ -238,7 +132,7 @@ const TYPED_GLOBALS: Array<[string, BuiltInType]> = [
        'from',
        addFunction(DEFAULT_SHAPES, [], {
          positionalParams: [
-            Effect.ConditionallyMutateIterator,
+            Effect.ConditionallyMutate,
            Effect.ConditionallyMutate,
            Effect.ConditionallyMutate,
          ],
@@ -478,150 +372,6 @@ const TYPED_GLOBALS: Array<[string, BuiltInType]> = [
      returnValueKind: ValueKind.Primitive,
    }),
  ],
-  [
-    'parseInt',
-    addFunction(DEFAULT_SHAPES, [], {
-      positionalParams: [],
-      restParam: Effect.Read,
-      returnType: {kind: 'Primitive'},
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    'parseFloat',
-    addFunction(DEFAULT_SHAPES, [], {
-      positionalParams: [],
-      restParam: Effect.Read,
-      returnType: {kind: 'Primitive'},
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    'isNaN',
-    addFunction(DEFAULT_SHAPES, [], {
-      positionalParams: [],
-      restParam: Effect.Read,
-      returnType: {kind: 'Primitive'},
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    'isFinite',
-    addFunction(DEFAULT_SHAPES, [], {
-      positionalParams: [],
-      restParam: Effect.Read,
-      returnType: {kind: 'Primitive'},
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    'encodeURI',
-    addFunction(DEFAULT_SHAPES, [], {
-      positionalParams: [],
-      restParam: Effect.Read,
-      returnType: {kind: 'Primitive'},
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    'encodeURIComponent',
-    addFunction(DEFAULT_SHAPES, [], {
-      positionalParams: [],
-      restParam: Effect.Read,
-      returnType: {kind: 'Primitive'},
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    'decodeURI',
-    addFunction(DEFAULT_SHAPES, [], {
-      positionalParams: [],
-      restParam: Effect.Read,
-      returnType: {kind: 'Primitive'},
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    'decodeURIComponent',
-    addFunction(DEFAULT_SHAPES, [], {
-      positionalParams: [],
-      restParam: Effect.Read,
-      returnType: {kind: 'Primitive'},
-      calleeEffect: Effect.Read,
-      returnValueKind: ValueKind.Primitive,
-    }),
-  ],
-  [
-    'Map',
-    addFunction(
-      DEFAULT_SHAPES,
-      [],
-      {
-        positionalParams: [Effect.ConditionallyMutateIterator],
-        restParam: null,
-        returnType: {kind: 'Object', shapeId: BuiltInMapId},
-        calleeEffect: Effect.Read,
-        returnValueKind: ValueKind.Mutable,
-      },
-      null,
-      true,
-    ),
-  ],
-  [
-    'Set',
-    addFunction(
-      DEFAULT_SHAPES,
-      [],
-      {
-        positionalParams: [Effect.ConditionallyMutateIterator],
-        restParam: null,
-        returnType: {kind: 'Object', shapeId: BuiltInSetId},
-        calleeEffect: Effect.Read,
-        returnValueKind: ValueKind.Mutable,
-      },
-      null,
-      true,
-    ),
-  ],
-  [
-    'WeakMap',
-    addFunction(
-      DEFAULT_SHAPES,
-      [],
-      {
-        positionalParams: [Effect.ConditionallyMutateIterator],
-        restParam: null,
-        returnType: {kind: 'Object', shapeId: BuiltInWeakMapId},
-        calleeEffect: Effect.Read,
-        returnValueKind: ValueKind.Mutable,
-      },
-      null,
-      true,
-    ),
-  ],
-  [
-    'WeakSet',
-    addFunction(
-      DEFAULT_SHAPES,
-      [],
-      {
-        positionalParams: [Effect.ConditionallyMutateIterator],
-        restParam: null,
-        returnType: {kind: 'Object', shapeId: BuiltInWeakSetId},
-        calleeEffect: Effect.Read,
-        returnValueKind: ValueKind.Mutable,
-      },
-      null,
-      true,
-    ),
-  ],
  // TODO: rest of Global objects
 ];

@@ -738,41 +488,6 @@ const REACT_APIS: Array<[string, BuiltInType]> = [
        calleeEffect: Effect.Read,
        hookKind: 'useEffect',
        returnValueKind: ValueKind.Frozen,
-        aliasing: {
-          receiver: '@receiver',
-          params: [],
-          rest: '@rest',
-          returns: '@returns',
-          temporaries: ['@effect'],
-          effects: [
-            // Freezes the function and deps
-            {
-              kind: 'Freeze',
-              value: '@rest',
-              reason: ValueReason.Effect,
-            },
-            // Internally creates an effect object that captures the function and deps
-            {
-              kind: 'Create',
-              into: '@effect',
-              value: ValueKind.Frozen,
-              reason: ValueReason.KnownReturnSignature,
-            },
-            // The effect stores the function and dependencies
-            {
-              kind: 'Capture',
-              from: '@rest',
-              into: '@effect',
-            },
-            // Returns undefined
-            {
-              kind: 'Create',
-              into: '@returns',
-              value: ValueKind.Primitive,
-              reason: ValueReason.KnownReturnSignature,
-            },
-          ],
-        },
      },
      BuiltInUseEffectHookId,
    ),
@@ -841,40 +556,13 @@ const REACT_APIS: Array<[string, BuiltInType]> = [
      {
        positionalParams: [],
        restParam: null,
-        returnType: {
-          kind: 'Function',
-          return: {kind: 'Poly'},
-          shapeId: BuiltInFireFunctionId,
-          isConstructor: false,
-        },
+        returnType: {kind: 'Primitive'},
        calleeEffect: Effect.Read,
        returnValueKind: ValueKind.Frozen,
      },
      BuiltInFireId,
    ),
  ],
-  [
-    'useEffectEvent',
-    addHook(
-      DEFAULT_SHAPES,
-      {
-        positionalParams: [],
-        restParam: Effect.Freeze,
-        returnType: {
-          kind: 'Function',
-          return: {kind: 'Poly'},
-          shapeId: BuiltinEffectEventId,
-          isConstructor: false,
-        },
-        calleeEffect: Effect.Read,
-        hookKind: 'useEffectEvent',
-        // Frozen because it should not mutate any locally-bound values
-        returnValueKind: ValueKind.Frozen,
-      },
-      BuiltInUseEffectEventId,
-    ),
-  ],
-  ['AUTODEPS', addObject(DEFAULT_SHAPES, BuiltInAutodepsId, [])],
 ];

 TYPED_GLOBALS.push(
@@ -1000,8 +688,6 @@ export function installTypeConfig(
        noAlias: typeConfig.noAlias === true,
        mutableOnlyIfOperandsAreMutable:
          typeConfig.mutableOnlyIfOperandsAreMutable === true,
-        aliasing: typeConfig.aliasing,
-        knownIncompatible: typeConfig.knownIncompatible ?? null,
      });
    }
    case 'hook': {
@@ -1019,8 +705,6 @@ export function installTypeConfig(
        ),
        returnValueKind: typeConfig.returnValueKind ?? ValueKind.Frozen,
        noAlias: typeConfig.noAlias === true,
-        aliasing: typeConfig.aliasing,
-        knownIncompatible: typeConfig.knownIncompatible ?? null,
      });
    }
    case 'object': {
@@ -1100,7 +784,7 @@ export function getReanimatedModuleType(registry: ShapeRegistry): ObjectType {
      addHook(registry, {
        positionalParams: [],
        restParam: Effect.Freeze,
-        returnType: {kind: 'Object', shapeId: ReanimatedSharedValueId},
+        returnType: {kind: 'Poly'},
        returnValueKind: ValueKind.Mutable,
        noAlias: true,
        calleeEffect: Effect.Read,
--- a/Show More
+++ b/Show More