Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/56922
Move `react-native/core-cli-utils` from `packages/` to `private/`, stop publishing it to npm, and reframe it as a reference implementation of React Native CLI tooling.
The package has no known external consumers and is only used internally by `private/helloworld/` and `packages/rn-tester/`. Publishing it to npm creates a maintenance surface for a package that serves no external users.
See https://github.com/react-native-community/discussions-and-proposals/pull/1002.
#### Changes
- Move `packages/core-cli-utils/` to `private/core-cli-utils/`.
- Convert all source files to CJS (require/module.exports) with Flow comment syntax (/*:: */), eliminating the runtime Babel dependency.
- Remove from the JS build pipeline (`scripts/build/config.js`).
- Remove the defunct `patchCoreCLIUtilsPackageJSON()` runtime patching from both `helloworld/cli.js` and `rn-tester/cli.js`, and delete both `monorepo.js` files that contained it.
- Add as `devDependency` to `rn-tester` and `helloworld`.
- Skip `"*"` version deps in `_prepareHelloWorld()` so they aren't rewritten to the Verdaccio-published version.
- Remove redundant desktop import ignore entry (`private/**` already covers it).
- Rewrite README as reference implementation documentation.
Changelog:
[General][Breaking] - The `react-native/core-cli-utils` package is no longer published. It remains available in the React Native repo as a reference implementation.
Reviewed By: cortinico
Differential Revision: D105959855
fbshipit-source-id: 42e439a45273bdeca76029eff306cdf2451308e2
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/56772
Upgrades to TypeScript 6.0.3 and updates `typescript-eslint/*` for TS 6.0 compatibility across `react-native` and `metro`.
#### Motivation
TypeScript 6.0 (Mar 2026) will resolve https://github.com/facebook/react-native/issues/53565. Before updating in the React Native CLI template, align in RN and Metro source for consistency.
This is an internal change since:
- This upgrade only applies to TS analysis of these repos' source code.
- Edits to `react-native/typescript-config/tsconfig.json` (which *is* distributed) maintain backwards compatibility.
#### Changes
**react-native**
- Bump `typescript` from `^5.8.3` to `^6.0.3`
- Bump `typescript-eslint/*` from `^8.24.0` to `^8.59.2`
- Replace deprecated `moduleResolution: "node"` with `"node16"` and `target: "es5"` with `"es2015"` in codegen-typescript-test
- Add explicit `types: ["jest", "node"]` where needed (TS 6.0 defaults `types` to `[]`)
- Set `strict: false` in configs that only enable specific strict flags (TS 6.0 defaults `strict` to `true`)
- Update `ModuleResolutionKind.NodeJs` to `Node16` in build config
**metro**
- Bump `typescript` from `5.8.3` to `^6.0.3`
- Bump `typescript-eslint/*` from `^8.36.0` to `^8.59.2`
- No tsconfig changes needed (`tsconfig/node20` preset is already TS 6.0 compatible)
Changelog: [Internal]
Reviewed By: christophpurrer
Differential Revision: D104658690
fbshipit-source-id: 9a2feeb257d5783431941a911b17065fcd0389a5
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/51840
Bumps the minimum version of Node.js in React Native to the current active LTS release (22.x, upgraded from 18.x which is now out of support).
- CI configurations are reduced from `[22, 20, 18]` to `[24, 22]`.
{F1978909878}
See https://nodejs.org/en/about/previous-releases.
Changelog:
[General][Breaking] - Our new minimum Node version is Node.js 22
Reviewed By: yungsters, cortinico
Differential Revision: D76037015
fbshipit-source-id: b6e4b3ee279a9a93d716a13297420bba73f45250
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/51688
Changelog: [Internal]
# Context
See D74904547.
## This diff
Creates the `react-native/debugger-shell` package, containing a basic implementation of an Electron-based shell for React Native DevTools. At this point, there is no direct dependency on the new package from the rest of React Native - it's designed to be used as part of a Meta-internal experimental rollout of the new debugger shell via the `BrowserLauncher` interface in `dev-middleware`.
Reviewed By: huntie
Differential Revision: D74820232
fbshipit-source-id: cb06ea9e2ed8c8822019cad8296cc19e69f9db0b
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/49340
This tool enables checking the boundary between JavaScript and Native for
backwards incompatible changes to protect against crashes.
This is useful for:
- Local Development
- Over the Air updates on platforms that support it
- Theoretically: Server Components with React Native
Check out the Readme for more information
Changelog: [General][Added] Open Sourcing React Native's Compatibility Check
Reviewed By: panagosg7
Differential Revision: D69476742
fbshipit-source-id: 8af6039839c5475c1258fa82d9750a9320cf0751
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/49311
This tool enables checking the boundary between JavaScript and Native for
backwards incompatible changes to protect against crashes.
This is useful for:
- Local Development
- Over the Air updates on platforms that support it
- Theoretically: Server Components with React Native
Check out the Readme for more information
Changelog: [General][Added] Open Sourcing React Native's Compatibility Check
Reviewed By: yungsters
Differential Revision: D69277991
fbshipit-source-id: 886a983d4b17609ce771cdd93b75f34bbd8417dc
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/44233
The package was added to our build scripts, but shouldn't have been. We're not exporting this package or making it public.
Changelog: [Internal]
This should unblock our OSS CI.
Reviewed By: cipolleschi
Differential Revision: D56513694
fbshipit-source-id: f37c75871253b2570fb933175165d8f0a9593a16
Summary:
This is a copy of the current packages/react-native/template that we exclusively use internally for testing.
Changelog: [Internal]
NOTE: Best contribution would be to scan the file list and ensure there isn't anything that shouldn't be in there.
bypass-github-export-checks
Reviewed By: cortinico, cipolleschi
Differential Revision: D56242484
fbshipit-source-id: 0913ff7acff9b0314b49f48e986674b77dbb908e
Summary:
Changelog: [Internal]
Use our build script for packages and to generate the TypeScript types.
bypass-github-export-checks
Reviewed By: huntie
Differential Revision: D54428870
fbshipit-source-id: 2a1666d30ac472300979b2be078a906d390e919a
Summary:
This adds `react-native/metro-config` to the monorepo build tool and emits the missing typescript declarations.
Right now, we do have typescript declarations on `metro-config`, but not `react-native/metro-config`. Which makes everything a bit harder extend from "[the default React Native metro config](https://github.com/facebook/react-native/pull/36502)" in Expo.
> Note, I also added the same `exports` block from `react-native/dev-middleware` for conformity.
One open question here is, why aren't we exporting _all_ helper functions from `metro-config`? To me, its a bit weird that we need both `metro-config` _and_ `react-native/metro-config` as `loadConfig` isn't exported.
## Changelog:
[INTERNAL] [FIXED] - Emit typescript declaration files for `react-native/metro-config`
Pull Request resolved: https://github.com/facebook/react-native/pull/41836
Test Plan:
Run the build tool, and check if the typescript declarations are emitted for `react-native/metro-config`.
```
yarn build metro-config
```
Reviewed By: hoxyq
Differential Revision: D51943453
Pulled By: huntie
fbshipit-source-id: cfaffe5660053fc9a9fcbe3dacf7f6ccc2bde01b
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/39540
This simplifies the use of Codegen when creating dev builds of `rn-tester` in the monorepo. It now runs from source for this internal scenario, and this package is now built using the shared monorepo build setup.
Changes:
- Migrate `packages/react-native-codegen` to the shared `yarn build` setup.
- Update package to use `"exports"` field and wrap entry point modules with `babel-register` (NOTE: This is only required for each entry point internally used in the monorepo).
- Fixup small Flow syntax quirks that fail under `hermes-parser`.
- Remove `BuildCodegenCLITask` task from Android build.
- Remove Codegen `build.sh` call from iOS build, use `require.resolve` for `combine-js-to-schema-cli.js` entry point.
Externally significant FYIs:
- `react-native/codegen` is converted to use the `"exports"` field — it should export all `.js` files, as before.
- `codegenPath` is now ignored and marked as deprecated on `ReactExtensions.kt`.
NOTE: TypeScript auto-generation is not yet enabled on this package, since it uses CommonJS `module.exports` syntax (unsupported by `flow-api-translator`).
Changelog: [Internal]
Reviewed By: cipolleschi
Differential Revision: D49370200
fbshipit-source-id: 992913155169912ea1a3cb24cb26efbd3f783058
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/38990
This PR adds auto-generation of Typescript definitions from Flow source code for packages using the shared monorepo build setup (https://github.com/facebook/react-native/pull/38718).
Today, these are the following Node.js packages:
- `packages/community-cli-plugin`
- `packages/dev-middleware` (⬅️ `emitTypeScriptDefs` enabled)
This also improves emitted Flow definitions (`.js.flow`), by using [`flow-api-translator`](https://www.npmjs.com/package/flow-api-translator) to strip implementations.
**All changes**
- Include `flow-api-translator` and configure this to emit type definitions as part of `yarn build`.
- Add translation from Flow source to TypeScript definitions (`.d.ts`) adjacent to each built file.
- Improve emitted Flow definitions (`.js.flow`), by using `flow-api-translator` to strip implementations (previously, source files were copied). The Flow and TS defs now mirror each other.
- Add `emitFlowDefs` and `emitTypeScriptDefs` options to build config to configure the above.
- Integrate TypeScript compiler to perform program validation on emitted `.d.ts` files.
- This is based on this guide: https://github.com/microsoft/TypeScript-wiki/blob/main/Using-the-Compiler-API.md#a-minimal-compiler.
- Throw an exception on the `rewritePackageExports` step if a package does not define an `"exports"` field.
- Add minimal `flow-typed` definitions for `typescript` 😄.
**Notes on [`flow-api-translator`](https://www.npmjs.com/package/flow-api-translator)**
This project is experimental but is in a more mature state than when we evaluated it earlier in 2023.
- It's now possible to run this tool on our new Node.js packages, since they are exclusively authored using `import`/`export` syntax (a requirement of the tool).
- As a safety net, we run the TypeScript compiler against the generated program, which will fail the build.
Changelog: [Internal]
Reviewed By: robhogan
Differential Revision: D48312463
fbshipit-source-id: 817edb35f911f52fa987946f2d8fc1a319078c9d
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/38795
## Context
RFC: Decoupling Flipper from React Native core: https://github.com/react-native-community/discussions-and-proposals/pull/641
## Changes
Inits new package `react-native/community-cli-plugin`. This migrates [`react-native-community/cli-plugin-metro`](https://github.com/react-native-community/cli/tree/main/packages/cli-plugin-metro) into the React Native repo, to enable faster iteration by the React Native core team. Specifically:
- This package contains several `metro` dependencies, which when removed from CLI will no longer require us to ship new CLI releases to get Metro patches and features to users.
- This package contains the `start`, `bundle`, and `ram-bundle` commands (central to the React Native development experience), for which we have incoming debugging-related changes.
- This package now **only** exports commands to be attached via a RN CLI plugin. With this move, we're aiming to **internalise** the default implementations of these dev commands within React Native — other RN CLI plugins can continue to override these, but must do so wholesale. (See also the recent fix for this: https://github.com/react-native-community/cli/pull/1999.)
In V15:
- (Microsoft feedback) Re-export `unstable_buildBundleWithConfig`, marking as unstable. This gives us a time buffer to consider how we repackage this functionality in future.
The package source has been converted from TypeScript to Flow, with a number of new `flow-typed/` defs added to meet type coverage requirements.
## To dos
- For now, we aren't removing the existing [`react-native-community/cli-plugin-metro`](https://github.com/react-native-community/cli/tree/main/packages/cli-plugin-metro) source — until later PRs consolidate this move by changing dependencies in the `react-native` package.
- **Exported API is reduced!**: I'm working with szymonrybczak to decouple references from RN CLI packages https://github.com/react-native-community/cli/pull/2021.
Changelog: [Internal]
Reviewed By: motiz88
Differential Revision: D46801501
fbshipit-source-id: 7f6b72941a69f487fb437768cdba125a9aa3418d
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/38718
> NOTE: Replaces https://github.com/facebook/react-native/pull/38240
## Context
RFC: Decoupling Flipper from React Native core: https://github.com/react-native-community/discussions-and-proposals/pull/641
## Changes
To support incoming new React Native packages around debugging (including migrating over [`react-native-community/cli-plugin-metro`](https://github.com/react-native-community/cli/tree/main/packages/cli-plugin-metro)) — which target Node.js and require a build step, this PR adds a minimal shared build setup across the `react-native` monorepo.
The setup is closely inspired/based on the build scripts in Jest, Metro, and React Native CLI — and is a simple set of script wrappers around Babel. These are available as build commands at the root of the repo:
- `yarn build` — Builds all configured packages. Functionally, this:
- Outputs a `dist/` directory with built files.
- Rewrites package.json `"exports"` to update every `./src/*` reference to `./dist/*` (source of truth).
- `scripts/build/babel-register.js` — Allows running all Node.js entry points from source, similar to the current setup in [facebook/metro](https://github.com/facebook/metro). (Example entry point file in this PR: `packages/dev-middleware/src/index.js`)
Build configuration (i.e. Babel config) is shared as a set standard across the monorepo, and **packages are opted-in to requiring a build**, configured in `scripts/build.config.js`.
```
const buildConfig /*: BuildConfig */ = {
// The packages to include for build and their build options
packages: {
'dev-middleware': {target: 'node'},
},
};
```
For now, there is a single `target: 'node'` option — this is necessary as `react-native`, unlike the above other projects, is a repository with packages targeting several runtimes. We may, in future, introduce a build step for other, non-Node, packages — which may be useful for things such as auto-generated TypeScript definitions.
{F1043312771}
**Differences from the Metro setup**
- References (and compiles out) repo-local `scripts/build/babel-register.js` — removing need for an npm-published dependency.
## Current integration points
- **CircleCI** — `yarn build` is added to the `build_npm_package` and `find_and_publish_bumped_packages` jobs.
**New Node.js package(s) are not load bearing quite yet**: There are not yet any built packages added to the dependencies of `packages/react-native/`, so this will be further tested in a later PR (and is actively being done in an internal commit stack).
### Alternative designs
**Per-package config file**
Replace `scripts/build/config.js` with a package-defined key in in `package.json`, similar to Jest's [`publishConfig`](https://github.com/jestjs/jest/blob/1f019afdcdfc54a6664908bb45f343db4e3d0848/packages/jest-cli/package.json#L87C3-L89C4).
```
"buildConfig": {
"type": "node"
},
```
This would be the only customisation required, with a single Babel config still standardised. Another option this might receive in future is `enableTypeScriptCodgeen`.
**Rollup**
More sophisticated build tool for Node.js, used by the React codebase (albeit within a custom script setup as well).
**Lerna and Nx**
- Most sophisticated setup enabling caching and optimised cloud runs.
- Probably the most likely thing we'll move towards at a later stage.
Changelog: [Internal]
Reviewed By: NickGerleman
Differential Revision: D47760330
fbshipit-source-id: 38ec94708ce3d9946a197d80885781e9707c5841
Alex Hunt