Enable Strict TS API by default (#57490)

Summary:
Pull Request resolved: #57490

See [**RFC0894: Removing deep imports from react-native**](react-native-community/discussions-and-proposals#894)

This is the **big switch** to enable the Strict TypeScript API (generated types + single index entry point) by default in React Native.

**Opt-in → opt-out**

After this change, the main `react-native` package resolves its `"types"` entry points only to `types_generated/index.d.ts` — with no other subpaths available.

The new `"react-native-legacy-deep-imports"` condition maps to legacy `types/` and `Libraries/*.d.ts` sources.

**Impact limitation**: For this stage of rollout, the `"default"` condition continues to resolve to source files. Only TypeScript is affected.

**How to opt out**

Opposite of today's opt-in, which we will update in [the docs](https://reactnative.dev/docs/strict-typescript-api). Again, the only impact area today is **TypeScript**.

```json5
// tsconfig.json
{
  "extends": "react-native/typescript-config",
  "compilerOptions": {
    ...
    "customConditions": ["react-native-legacy-deep-imports"]
  }
}
```

**Other changes**

- Drop `react-native/typescript-config/strict` entry point, update README.
- Update `__typetests__`.

**Rollout plan**

**Target release: 0.87**. This and the contributing stack will be cherry picked for RC1.

- We've conducted testing against 100+ real Expo codebases, giving us the confidence that we've reduced breaking changes enough that the vast majority of RN codebases can migrate.
- The Strict API includes a number of **intentional breaking changes**, and docs have been kept up to date.
- We're shipping a `/migrate-to-strict-api` skill to migrate via agents, see react-native-community/skills#3.

**What's improved since 0.80?**

Since the initial opt-in launch of the Strict API in 0.80, we've been making continuous improvements over the last year to get our generated types into a widely launchable state.

Most notably:

- 21+ new/updated root APIs and fixes due to community feedback ([discussion](react-native-community/discussions-and-proposals#893), [PRs](https://github.com/react/react-native/pulls?q=is%3Apr%20label%3A%22JS%20API%20stabilization%20(1.0)%22%20is%3Aclosed)).
- Upstream encapsulation blocker in TypeScript, fixed in 6.0 (#53565).
- Tailwind/Uniwind compatibility (`interface` types for props).
- `*Instance` ref type exports for all built-in components (react-native-community/discussions-and-proposals#1003).
- Fixes to previously mistyped, high impact APIs, such as `Appearance`.
- New subpath entry points for `asset-registry`, `setup-env`, and others.
- Refinements to doc comments/type translation build.

**Rollback plan**

Revert this diff.

IMPORTANT: We'll adopt a policy of **super-eager rollback**, if there are any unsolvable issues during the RC phase.

Changelog:
[General][Breaking] - React Native's default JavaScript API is now the [Strict TypeScript API](https://reactnative.dev/docs/strict-typescript-api). Use `customConditions: ["react-native-legacy-deep-imports"]` to opt out.

Reviewed By: cortinico

Differential Revision: D110458670

fbshipit-source-id: 4b0e0b458a5f895f783d6d936e7b11ccff2df076

Author: huntie

.github/workflows/test-all.yml

@@ -471,9 +471,9 @@ jobs:
       - name: Flow
         shell: bash
         run: yarn flow-check
-      - name: TypeScript
+      - name: TypeScript (legacy deep imports / manual types)
         shell: bash
-        run: yarn test-typescript
+        run: yarn test-typescript-legacy
 
   test_js:
     runs-on: ubuntu-latest

package.json

@@ -33,8 +33,8 @@
     "test-release-local-clean": "node ./scripts/release-testing/test-release-local-clean.js",
     "test-release-local": "node ./scripts/release-testing/test-release-local.js",
     "test-ios": "./scripts/objc-test.sh test",
-    "test-typescript": "tsc -p packages/react-native/types/tsconfig.json",
-    "test-generated-typescript": "tsc -p packages/react-native/types_generated/tsconfig.test.json",
+    "test-typescript-legacy": "tsc -p packages/react-native/__typetests__/tsconfig.legacy.json",
+    "test-generated-typescript": "tsc -p packages/react-native/__typetests__/tsconfig.json",
     "test": "jest",
     "fantom": "./scripts/fantom.sh",
     "fantom-cli": "./scripts/fantom-cli.sh",

…build-types/templates/tsconfig.test.json …react-native/__typetests__/tsconfig.jsonscripts/js-api/build-types/templates/tsconfig.test.json renamed to packages/react-native/__typetests__/tsconfig.json scripts/js-api/build-types/templates/tsconfig.test.json renamed to packages/react-native/__typetests__/tsconfig.json

@@ -1,4 +1,5 @@
 {
+  "$schema": "https://json.schemastore.org/tsconfig",
   "compilerOptions": {
     "module": "esnext",
     "lib": ["es2020"],
@@ -9,9 +10,7 @@
     "jsx": "react",
     "noEmit": true,
     "forceConsistentCasingInFileNames": true,
-    "paths": {"react-native": ["."]},
-    "moduleResolution": "bundler",
-    "customConditions": ["react-native-strict-api"]
+    "moduleResolution": "bundler"
   },
-  "include": ["**/*.d.ts", "../__typetests__/**/*"]
+  "include": ["**/*"]
 }

packages/react-native/__typetests__/tsconfig.legacy.json

@@ -0,0 +1,10 @@
+{
+  "$schema": "https://json.schemastore.org/tsconfig",
+  // Legacy variant: Opts into the `"react-native-legacy-deep-imports"` export
+  // condition so `react-native` and `react-native/Libraries/*` resolve to the
+  // hand-written types in `types/`.
+  "extends": "./tsconfig.json",
+  "compilerOptions": {
+    "customConditions": ["react-native-legacy-deep-imports"]
+  }
+}

packages/react-native/package.json

@@ -27,20 +27,19 @@
     "react-native": "cli.js"
   },
   "main": "./index.js",
-  "types": "types",
   "exports": {
     ".": {
-      "react-native-strict-api": "./types_generated/index.d.ts",
-      "types": "./types/index.d.ts",
+      "react-native-legacy-deep-imports": "./types/index.d.ts",
+      "types": "./types_generated/index.d.ts",
       "default": "./index.js"
     },
     "./Libraries/*": {
-      "react-native-strict-api": null,
-      "types": "./Libraries/*.d.ts",
+      "react-native-legacy-deep-imports": "./Libraries/*.d.ts",
+      "types": null,
       "default": "./Libraries/*.js"
     },
     "./Libraries/*.js": {
-      "react-native-strict-api": null,
+      "types": null,
       "default": "./Libraries/*.js"
     },
     "./scripts/*": "./scripts/*",

packages/react-native/types/tsconfig.json

@@ -9,25 +9,18 @@ This package provides the default `tsconfig.json` used by newly built React Nati
 
 This template is customized for specific versions of React Native, and should be updated in sync with the rest of your app.
 
-## Strict TypeScript API
+## Opting out of the Strict TypeScript API (default in 0.87)
 
-To opt into the new [strict TypeScript API](https://reactnative.dev/blog/2025/06/12/moving-towards-a-stable-javascript-api#strict-typescript-api-opt-in) you can extend from `@react-native/typescript-config/strict`
+To opt out of the new [Strict TypeScript API](https://reactnative.dev/docs/strict-typescript-api) you can extend from `@react-native/typescript-config/strict`
 
-```jsonc
-{
-  "extends": "@react-native/typescript-config/strict",
-  // ...
-}
-```
-
-or alternatively add the `customConditions` yourself:
+If your app still needs access to deep `'react-native/Libraries/*'` imports (deprecated in 0.80), you can opt out via `customConditions` in your `tsconfig.json`:
 
 ```jsonc
 {
   "extends": "@react-native/typescript-config",
   "compilerOptions": {
     // ...
-    "customConditions": ["react-native-strict-api", "react-native"]
+    "customConditions": ["react-native", "react-native-legacy-deep-imports"]
   }
 }
 ```

packages/typescript-config/README.md

@@ -16,7 +16,6 @@
   ],
   "bugs": "https://github.com/react/react-native/issues",
   "exports": {
-    ".": "./tsconfig.json",
-    "./strict": "./tsconfig.strict.json"
+    ".": "./tsconfig.json"
   }
 }

packages/typescript-config/package.json

@@ -21,8 +21,8 @@
   },
   "exports": {
     ".": {
-      "react-native-strict-api": "./types_generated/index.d.ts",
-      "types": "./index.d.ts",
+      "react-native-legacy-deep-imports": "./index.d.ts",
+      "types": "./types_generated/index.d.ts",
       "default": "./index.js"
     },
     "./*": {