diff --git a/.flowconfig b/.flowconfig
index 1faa6debeb19..96277a41df5f 100644
--- a/.flowconfig
+++ b/.flowconfig
@@ -69,6 +69,11 @@ munge_underscores=true
 module.name_mapper='^react-native$' -> '<PROJECT_ROOT>/packages/react-native/index.js'
 module.name_mapper='^react-native/\(.*\)$' -> '<PROJECT_ROOT>/packages/react-native/\1'
 module.name_mapper='^@react-native/dev-middleware$' -> '<PROJECT_ROOT>/packages/dev-middleware'
+; [macOS] Resolve workspace self-references (incl. @react-native/fantom) in yarn pnpm mode
+module.name_mapper='^@react-native/fantom$' -> '<PROJECT_ROOT>/private/react-native-fantom/src/index.js'
+module.name_mapper='^@react-native/fantom/\(.*\)$' -> '<PROJECT_ROOT>/private/react-native-fantom/\1'
+module.name_mapper='^@react-native/core-cli-utils$' -> '<PROJECT_ROOT>/packages/core-cli-utils/src/index.flow.js'
+; macOS]
 module.name_mapper='^@?[./a-zA-Z0-9$_-]+\.\(bmp\|gif\|jpg\|jpeg\|png\|psd\|svg\|webp\|m4v\|mov\|mp4\|mpeg\|mpg\|webm\|aac\|aiff\|caf\|m4a\|mp3\|wav\|html\|pdf\|xml\)$' -> '<PROJECT_ROOT>/packages/react-native/Libraries/Image/RelativeImageStub'
 
 module.system.haste.module_ref_prefix=m#
diff --git a/.prettierrc b/.prettierrc
index a3f4c89ec6a2..91d36cb6e41e 100644
--- a/.prettierrc
+++ b/.prettierrc
@@ -6,6 +6,7 @@
   "singleQuote": true,
   "trailingComma": "all",
   "endOfLine": "lf",
+  "plugins": ["prettier-plugin-hermes-parser"],
   "overrides": [
     {
       "files": ["*.code-workspace"],
diff --git a/.yarnrc.yml b/.yarnrc.yml
index 2d4e1303d05c..2fb7124f02d3 100644
--- a/.yarnrc.yml
+++ b/.yarnrc.yml
@@ -1,7 +1,44 @@
 enableScripts: false
 
-nodeLinker: node-modules
+nodeLinker: pnpm # [macOS]
 
 npmMinimalAgeGate: 7d
 
 yarnPath: .yarn/releases/yarn-4.12.0.cjs
+
+# [macOS] Declare direct dependencies that upstream package manifests omit and that
+# were previously resolved via a hoisted node_modules. In yarn pnpm mode the strict,
+# non-hoisted layout requires them. Centralizing them here keeps the upstream-tracked
+# manifests pristine. Third-party only: yarn.config.cjs constraints don't govern
+# packageExtensions, so no @react-native/* deps belong here (they must stay in a
+# manifest to remain under release-branch version-pinning).
+packageExtensions:
+  "@react-native/codegen@*":
+    dependencies:
+      "@babel/parser": "^7.25.2"
+  "@react-native/babel-plugin-codegen@*":
+    dependencies:
+      "@babel/plugin-syntax-flow": "^7.25.0"
+  "@react-native/core-cli-utils@*":
+    dependencies:
+      "metro": "^0.82.5"
+  "@react-native/metro-babel-transformer@*":
+    dependencies:
+      "metro-babel-transformer": "^0.82.5"
+  "@react-native/compatibility-check@*":
+    dependencies:
+      "invariant": "^2.2.4"
+  "@react-native/tester@*":
+    dependencies:
+      "metro-config": "^0.82.5"
+  "@react-native/eslint-plugin-monorepo@*":
+    dependencies:
+      "hermes-estree": "0.29.1"
+  "@react-native/fantom@*":
+    dependencies:
+      "jest-docblock": "^29.7.0"
+      "jest-message-util": "^29.7.0"
+      "metro": "^0.82.5"
+      "metro-config": "^0.82.5"
+      "source-map": "^0.6.1"
+# macOS]
diff --git a/docsite/.yarnrc.yml b/docsite/.yarnrc.yml
new file mode 100644
index 000000000000..dc4cc3e1cf71
--- /dev/null
+++ b/docsite/.yarnrc.yml
@@ -0,0 +1,2 @@
+# Keep the standalone docsite on node-modules; Docusaurus needs hoisted deps.
+nodeLinker: node-modules
diff --git a/package.json b/package.json
index 52efcc047118..81e9d164210e 100644
--- a/package.json
+++ b/package.json
@@ -53,18 +53,28 @@
     "@babel/core": "^7.25.2",
     "@babel/eslint-parser": "^7.25.1",
     "@babel/generator": "^7.25.0",
+    "@babel/parser": "^7.25.2",
     "@babel/plugin-syntax-typescript": "^7.25.4",
     "@babel/plugin-transform-regenerator": "^7.24.7",
     "@babel/preset-env": "^7.25.3",
     "@babel/preset-flow": "^7.24.7",
+    "@babel/runtime": "^7.25.2",
+    "@babel/traverse": "^7.25.2",
+    "@babel/types": "^7.25.2",
     "@changesets/cli": "^2.28.1",
     "@electron/packager": "^18.3.6",
     "@jest/create-cache-key-function": "^29.7.0",
     "@microsoft/api-extractor": "^7.52.2",
+    "@react-native/babel-preset": "workspace:*",
+    "@react-native/eslint-config": "workspace:*",
+    "@react-native/eslint-plugin": "workspace:*",
+    "@react-native/eslint-plugin-monorepo": "workspace:*",
+    "@react-native/eslint-plugin-specs": "workspace:*",
     "@react-native/metro-babel-transformer": "workspace:*",
     "@react-native/metro-config": "workspace:*",
     "@tsconfig/node22": "22.0.2",
     "@types/react": "^19.1.0",
+    "@typescript-eslint/eslint-plugin": "^7.1.1",
     "@typescript-eslint/parser": "^7.1.1",
     "@yarnpkg/types": "^4.0.1",
     "ansi-styles": "^4.2.1",
@@ -84,6 +94,7 @@
     "eslint-plugin-jest": "^27.9.0",
     "eslint-plugin-jsx-a11y": "^6.6.0",
     "eslint-plugin-react": "^7.30.1",
+    "eslint-plugin-react-hooks": "^5.2.0",
     "eslint-plugin-react-native": "^4.0.0",
     "eslint-plugin-redundant-undefined": "^0.4.0",
     "eslint-plugin-relay": "^1.8.3",
@@ -91,6 +102,7 @@
     "flow-bin": "^0.275.0",
     "glob": "^7.1.1",
     "hermes-eslint": "0.29.1",
+    "hermes-estree": "0.29.1",
     "hermes-transform": "0.29.1",
     "inquirer": "^7.1.0",
     "jest": "^29.7.0",
@@ -98,9 +110,12 @@
     "jest-diff": "^29.7.0",
     "jest-junit": "^10.0.0",
     "jest-snapshot": "^29.7.0",
+    "jsonc-eslint-parser": "^2.3.0",
     "markdownlint-cli2": "^0.22.0",
     "markdownlint-rule-relative-links": "^3.0.0",
+    "metro": "^0.82.5",
     "metro-babel-register": "^0.82.5",
+    "metro-config": "^0.82.5",
     "metro-memory-fs": "^0.82.5",
     "metro-transform-plugins": "^0.82.5",
     "micromatch": "^4.0.4",
@@ -118,6 +133,7 @@
     "tinybench": "^3.1.0",
     "typescript": "5.8.3",
     "ws": "^6.2.3",
+    "yargs": "^17.6.2",
     "zx": "^8.2.4"
   },
   "resolutions": {
diff --git a/packages/rn-tester/metro.config.js b/packages/rn-tester/metro.config.js
index 445adfde474a..7ed5386ac94c 100644
--- a/packages/rn-tester/metro.config.js
+++ b/packages/rn-tester/metro.config.js
@@ -39,6 +39,7 @@ const config = {
     blockList: [/..\/react-native\/sdks\/hermes/],
     extraNodeModules: {
       'react-native': path.resolve(__dirname, '../react-native'),
+      'react-native-macos': path.resolve(__dirname, '../react-native'), // [macOS] resolve the react-native -> react-native-macos redirect in yarn pnpm mode
     },
     platforms: ['ios', 'macos', 'android'], // [macOS]
   },
diff --git a/yarn.lock b/yarn.lock
index 305e0c9812e4..d5f250b9a590 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -387,7 +387,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@babel/parser@npm:^7.29.7":
+"@babel/parser@npm:^7.25.2, @babel/parser@npm:^7.29.7":
   version: 7.29.7
   resolution: "@babel/parser@npm:7.29.7"
   dependencies:
@@ -566,6 +566,17 @@ __metadata:
   languageName: node
   linkType: hard
 
+"@babel/plugin-syntax-flow@npm:^7.25.0":
+  version: 7.29.7
+  resolution: "@babel/plugin-syntax-flow@npm:7.29.7"
+  dependencies:
+    "@babel/helper-plugin-utils": "npm:^7.29.7"
+  peerDependencies:
+    "@babel/core": ^7.0.0-0
+  checksum: 10c0/b2e330dd0dc535c7364937ce2b29a06065e60b1d523db75f36ab4fb89e4ba664e2230cbb1937b35712c9a0ebafc3358f323d6e6b22247d5ebad12fdd3e1f6e98
+  languageName: node
+  linkType: hard
+
 "@babel/plugin-syntax-import-assertions@npm:^7.26.0":
   version: 7.26.0
   resolution: "@babel/plugin-syntax-import-assertions@npm:7.26.0"
@@ -1543,6 +1554,13 @@ __metadata:
   languageName: node
   linkType: hard
 
+"@babel/runtime@npm:^7.25.2":
+  version: 7.29.7
+  resolution: "@babel/runtime@npm:7.29.7"
+  checksum: 10c0/ca11572f7146b21e0bde6a9ed4bb6a89eafbee5f0944c7eb54d0d8a2dac962c33638a1d611e14faa71dfbb92b4b5f9236232208568a6b7d5c6f3f39ddb91771e
+  languageName: node
+  linkType: hard
+
 "@babel/template@npm:^7.25.0, @babel/template@npm:^7.25.9, @babel/template@npm:^7.27.2, @babel/template@npm:^7.3.3":
   version: 7.27.2
   resolution: "@babel/template@npm:7.27.2"
@@ -1580,6 +1598,21 @@ __metadata:
   languageName: node
   linkType: hard
 
+"@babel/traverse@npm:^7.25.2, @babel/traverse@npm:^7.29.7":
+  version: 7.29.7
+  resolution: "@babel/traverse@npm:7.29.7"
+  dependencies:
+    "@babel/code-frame": "npm:^7.29.7"
+    "@babel/generator": "npm:^7.29.7"
+    "@babel/helper-globals": "npm:^7.29.7"
+    "@babel/parser": "npm:^7.29.7"
+    "@babel/template": "npm:^7.29.7"
+    "@babel/types": "npm:^7.29.7"
+    debug: "npm:^4.3.1"
+  checksum: 10c0/e256a1fbdb956555b76f3c285b1e453f6bedec8b3afb61751d99d933efd11c7d79caf5ddf2493570058a9f7deaa1b48324380d7c1aa1443fd9508becbf56331a
+  languageName: node
+  linkType: hard
+
 "@babel/traverse@npm:^7.25.3, @babel/traverse@npm:^7.25.9, @babel/traverse@npm:^7.27.1, @babel/traverse@npm:^7.28.3, @babel/traverse@npm:^7.28.4":
   version: 7.28.4
   resolution: "@babel/traverse@npm:7.28.4"
@@ -1595,21 +1628,6 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@babel/traverse@npm:^7.29.7":
-  version: 7.29.7
-  resolution: "@babel/traverse@npm:7.29.7"
-  dependencies:
-    "@babel/code-frame": "npm:^7.29.7"
-    "@babel/generator": "npm:^7.29.7"
-    "@babel/helper-globals": "npm:^7.29.7"
-    "@babel/parser": "npm:^7.29.7"
-    "@babel/template": "npm:^7.29.7"
-    "@babel/types": "npm:^7.29.7"
-    debug: "npm:^4.3.1"
-  checksum: 10c0/e256a1fbdb956555b76f3c285b1e453f6bedec8b3afb61751d99d933efd11c7d79caf5ddf2493570058a9f7deaa1b48324380d7c1aa1443fd9508becbf56331a
-  languageName: node
-  linkType: hard
-
 "@babel/types@npm:^7.0.0, @babel/types@npm:^7.20.7, @babel/types@npm:^7.25.2, @babel/types@npm:^7.25.9, @babel/types@npm:^7.26.7, @babel/types@npm:^7.27.1, @babel/types@npm:^7.27.3, @babel/types@npm:^7.28.2, @babel/types@npm:^7.28.4, @babel/types@npm:^7.3.3, @babel/types@npm:^7.4.4":
   version: 7.28.4
   resolution: "@babel/types@npm:7.28.4"
@@ -3075,18 +3093,28 @@ __metadata:
     "@babel/core": "npm:^7.25.2"
     "@babel/eslint-parser": "npm:^7.25.1"
     "@babel/generator": "npm:^7.25.0"
+    "@babel/parser": "npm:^7.25.2"
     "@babel/plugin-syntax-typescript": "npm:^7.25.4"
     "@babel/plugin-transform-regenerator": "npm:^7.24.7"
     "@babel/preset-env": "npm:^7.25.3"
     "@babel/preset-flow": "npm:^7.24.7"
+    "@babel/runtime": "npm:^7.25.2"
+    "@babel/traverse": "npm:^7.25.2"
+    "@babel/types": "npm:^7.25.2"
     "@changesets/cli": "npm:^2.28.1"
     "@electron/packager": "npm:^18.3.6"
     "@jest/create-cache-key-function": "npm:^29.7.0"
     "@microsoft/api-extractor": "npm:^7.52.2"
+    "@react-native/babel-preset": "workspace:*"
+    "@react-native/eslint-config": "workspace:*"
+    "@react-native/eslint-plugin": "workspace:*"
+    "@react-native/eslint-plugin-monorepo": "workspace:*"
+    "@react-native/eslint-plugin-specs": "workspace:*"
     "@react-native/metro-babel-transformer": "workspace:*"
     "@react-native/metro-config": "workspace:*"
     "@tsconfig/node22": "npm:22.0.2"
     "@types/react": "npm:^19.1.0"
+    "@typescript-eslint/eslint-plugin": "npm:^7.1.1"
     "@typescript-eslint/parser": "npm:^7.1.1"
     "@yarnpkg/types": "npm:^4.0.1"
     ansi-styles: "npm:^4.2.1"
@@ -3106,6 +3134,7 @@ __metadata:
     eslint-plugin-jest: "npm:^27.9.0"
     eslint-plugin-jsx-a11y: "npm:^6.6.0"
     eslint-plugin-react: "npm:^7.30.1"
+    eslint-plugin-react-hooks: "npm:^5.2.0"
     eslint-plugin-react-native: "npm:^4.0.0"
     eslint-plugin-redundant-undefined: "npm:^0.4.0"
     eslint-plugin-relay: "npm:^1.8.3"
@@ -3113,6 +3142,7 @@ __metadata:
     flow-bin: "npm:^0.275.0"
     glob: "npm:^7.1.1"
     hermes-eslint: "npm:0.29.1"
+    hermes-estree: "npm:0.29.1"
     hermes-transform: "npm:0.29.1"
     inquirer: "npm:^7.1.0"
     jest: "npm:^29.7.0"
@@ -3120,9 +3150,12 @@ __metadata:
     jest-diff: "npm:^29.7.0"
     jest-junit: "npm:^10.0.0"
     jest-snapshot: "npm:^29.7.0"
+    jsonc-eslint-parser: "npm:^2.3.0"
     markdownlint-cli2: "npm:^0.22.0"
     markdownlint-rule-relative-links: "npm:^3.0.0"
+    metro: "npm:^0.82.5"
     metro-babel-register: "npm:^0.82.5"
+    metro-config: "npm:^0.82.5"
     metro-memory-fs: "npm:^0.82.5"
     metro-transform-plugins: "npm:^0.82.5"
     micromatch: "npm:^4.0.4"
@@ -3140,6 +3173,7 @@ __metadata:
     tinybench: "npm:^3.1.0"
     typescript: "npm:5.8.3"
     ws: "npm:^6.2.3"
+    yargs: "npm:^17.6.2"
     zx: "npm:^8.2.4"
   languageName: unknown
   linkType: soft
@@ -3374,7 +3408,7 @@ __metadata:
   languageName: unknown
   linkType: soft
 
-"@react-native/eslint-config@workspace:packages/eslint-config-react-native":
+"@react-native/eslint-config@workspace:*, @react-native/eslint-config@workspace:packages/eslint-config-react-native":
   version: 0.0.0-use.local
   resolution: "@react-native/eslint-config@workspace:packages/eslint-config-react-native"
   dependencies:
@@ -3398,7 +3432,7 @@ __metadata:
   languageName: unknown
   linkType: soft
 
-"@react-native/eslint-plugin-monorepo@workspace:private/eslint-plugin-monorepo":
+"@react-native/eslint-plugin-monorepo@workspace:*, @react-native/eslint-plugin-monorepo@workspace:private/eslint-plugin-monorepo":
   version: 0.0.0-use.local
   resolution: "@react-native/eslint-plugin-monorepo@workspace:private/eslint-plugin-monorepo"
   dependencies:
@@ -3406,7 +3440,7 @@ __metadata:
   languageName: unknown
   linkType: soft
 
-"@react-native/eslint-plugin-specs@workspace:packages/eslint-plugin-specs":
+"@react-native/eslint-plugin-specs@workspace:*, @react-native/eslint-plugin-specs@workspace:packages/eslint-plugin-specs":
   version: 0.0.0-use.local
   resolution: "@react-native/eslint-plugin-specs@workspace:packages/eslint-plugin-specs"
   dependencies:
@@ -10064,7 +10098,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"metro-babel-transformer@npm:0.82.5":
+"metro-babel-transformer@npm:0.82.5, metro-babel-transformer@npm:^0.82.5":
   version: 0.82.5
   resolution: "metro-babel-transformer@npm:0.82.5"
   dependencies: