demo: Add cache GC measurement harnesses (Node, browser, Android)

.circleci/config.yml

@@ -123,12 +123,7 @@ jobs:
       - run:
           name: Add examples/* to yarn workspace
           command: |
-            npm pkg delete workspaces[6]
-            npm pkg delete workspaces[5]
-            npm pkg delete workspaces[4]
-            npm pkg delete workspaces[3]
-            npm pkg delete workspaces[2]
-            npm pkg delete workspaces[1]
+            npm pkg set workspaces="$(node -p "JSON.stringify(require('./package.json').workspaces.filter(w => !w.startsWith('examples/') && w !== 'website'))")" --json
             npm pkg set 'workspaces[]'='examples/todo-app'
             npm pkg set 'workspaces[]'='examples/github-app'
             npm pkg set 'workspaces[]'='examples/normalizr-relationships'

.cursor/rules/ci-config.mdc

@@ -19,7 +19,7 @@ alwaysApply: false
   - `esmodule-types` also runs `examples/todo-app/tsconfig.typetest-libcheck.json` (`skipLibCheck: false`, `types: []`) so errors inside the legacy outputs fail CI, and `esmodule-types-latest` runs it with `--moduleResolution bundler` (TS 7 removed `node`) to cover `lib/`; the other typetests use `skipLibCheck: true`.
   - Any change to legacy types building must leave `ts*/` output byte-identical to master (diff it) unless it intentionally changes published types (then add a changeset).
 - Never `git fetch --depth` the base branch in the relevance check: a shallow fetch severs the merge base and the three-dot diff fails.
-- Changing root `package.json` `workspaces` requires updating the `setup` job's workspace trimming step.
+- The `setup` job trims root `workspaces` by name (drops `examples/*` and `website`, keeps the rest). A new workspace outside those is kept in every CircleCI job; update the filter if it should not be.
 
 ## GitHub Actions (`.github/workflows/`)
 

.github/workflows/benchmark-react.yml

@@ -10,6 +10,7 @@ on:
       - 'packages/endpoint/src/schemas/**'
       - 'packages/normalizr/src/**'
       - 'examples/benchmark-react/**'
+      - 'examples/gc-shared/**'
       - '.github/workflows/benchmark-react.yml'
   push:
     branches:
@@ -20,6 +21,7 @@ on:
       - 'packages/endpoint/src/schemas/**'
       - 'packages/normalizr/src/**'
       - 'examples/benchmark-react/**'
+      - 'examples/gc-shared/**'
       - '.github/workflows/benchmark-react.yml'
 
 concurrency:

.github/workflows/benchmark.yml

@@ -9,6 +9,7 @@ on:
       - 'packages/endpoint/src/schemas/**'
       - 'packages/core/src/**'
       - 'examples/benchmark/**'
+      - 'examples/gc-shared/**'
       - '.github/workflows/benchmark.yml'
   push:
     branches:
@@ -18,6 +19,7 @@ on:
       - 'packages/endpoint/src/schemas/**'
       - 'packages/core/src/**'
       - 'examples/benchmark/**'
+      - 'examples/gc-shared/**'
       - '.github/workflows/benchmark.yml'
 permissions:
   contents: write

AGENTS.md

@@ -22,12 +22,14 @@ Monorepo for `@data-client` high performance npm packages.
 
 **Targeted tests**: `yarn test --selectProjects ReactDOM --testPathPatterns packages/react` (project names: `ReactDOM`, `Node`, `ReactNative`)
 
+**Other React versions** (CI runs `^17`, `^18`, `19.3`): never swap versions in the main checkout. In a throwaway `git worktree`: `yarn install`, `yarn run ci:build:setup`, then the matching `npm pkg delete resolutions.*` + `yarn up ...` lines from the `unit_tests` job in `.circleci/config.yml`, then `yarn test --no-cache ...`. Without `--no-cache`, transforms cached before types were built leave `const enum` members (e.g. `ExpiryStatus.Valid`) undefined; that looks like a version failure but isn't. React 17's legacy Suspense keeps hidden content beside the fallback in `textContent`.
+
 ## CI
 
 - **CircleCI** (`.circleci/config.yml`) — PR validation: lint, typecheck, unit tests (React 17/18/native/latest), Node matrix, ESM type checks (TS 4.0–5.3+), browser build.
 - **GitHub Actions** (`.github/workflows/`) — release (`changesets`), bundle size PR comments, benchmark regression detection.
 
-Changing root `package.json` `workspaces` requires updating `.circleci/config.yml` (`setup` job) and `.github/workflows/` install steps.
+Adding a root `package.json` workspace outside `examples/` or `website` requires updating `.circleci/config.yml` (`setup` job trims by name) and `.github/workflows/` install steps.
 
 ## Changesets
 

eslint.config.mjs

@@ -62,6 +62,24 @@ export default [
       },
     },
   },
+  // Node CommonJS: configs, host scripts, and the GC harness shared modules
+  {
+    files: [
+      '**/*.cjs',
+      'examples/gc-shared/**/*.js',
+      'examples/benchmark-native/*.config.js',
+      'examples/benchmark-native/.prettierrc.js',
+      'examples/benchmark-native/scripts/**',
+    ],
+    languageOptions: {
+      sourceType: 'commonjs',
+      globals: globals.node,
+    },
+    rules: {
+      // `const crypto = require('crypto')` shadows Node's global by design
+      'no-redeclare': ['error', { builtinGlobals: false }],
+    },
+  },
   {
     files: ['examples/**/*.?(m|c)ts?(x)'],
     rules: {

examples/AGENTS.md

@@ -4,7 +4,11 @@
 
 ### Monorepo workspace members
 
-`benchmark`, `benchmark-react`, `test-bundlesize`, `normalizr-*`, `coin-app` — listed in root `package.json` workspaces, managed by yarn. Most use `workspace:*` for `@data-client/*` deps.
+`benchmark`, `benchmark-react`, `benchmark-native`, `test-bundlesize`, `normalizr-*`, `coin-app` — listed in root `package.json` workspaces, managed by yarn. Most use `workspace:*` for `@data-client/*` deps. `benchmark-native` (React Native Android) uses the root Jest/ESLint/TypeScript toolchain and is not installed in CI.
+
+### Shared (non-workspace) code
+
+`gc-shared` — CommonJS `.js` + hand-written `.d.ts` shared by the GC harnesses in `benchmark`, `benchmark-react`, and `benchmark-native`. No `package.json` on purpose (see its README); include it in each harness's build-provenance inputs.
 
 ### Standalone (StackBlitz demos)
 
@@ -22,4 +26,4 @@
 
 ## Build Tooling
 
-Most examples use Webpack via `@anansi/webpack-config`. Exceptions: `nextjs` (Next.js), `vue-todo-app` (Vite), `normalizr-*` (Node scripts via `babel-node`).
+Most examples use Webpack via `@anansi/webpack-config`. Exceptions: `nextjs` (Next.js), `vue-todo-app` (Vite), `normalizr-*` (Node scripts via `babel-node`), `benchmark-native` (Metro).

examples/benchmark-native/.gitignore

@@ -0,0 +1,85 @@
+# OSX
+#
+.DS_Store
+
+# Xcode
+#
+build/
+*.pbxuser
+!default.pbxuser
+*.mode1v3
+!default.mode1v3
+*.mode2v3
+!default.mode2v3
+*.perspectivev3
+!default.perspectivev3
+xcuserdata
+*.xccheckout
+*.moved-aside
+DerivedData
+*.hmap
+*.ipa
+*.xcuserstate
+**/.xcode.env.local
+
+# Android/IntelliJ
+#
+build/
+.idea
+.gradle
+local.properties
+*.iml
+*.hprof
+.cxx/
+*.keystore
+!debug.keystore
+.kotlin/
+
+# node.js
+#
+node_modules/
+npm-debug.log
+yarn-error.log
+
+# fastlane
+#
+# It is recommended to not store the screenshots in the git repo. Instead, use fastlane to re-generate the
+# screenshots whenever they are needed.
+# For more information about the recommended setup visit:
+# https://docs.fastlane.tools/best-practices/source-control/
+
+**/fastlane/report.xml
+**/fastlane/Preview.html
+**/fastlane/screenshots
+**/fastlane/test_output
+
+# Bundle artifact
+*.jsbundle
+
+# Ruby / CocoaPods
+**/Pods/
+/vendor/bundle/
+
+# Temporary files created by Metro to check the health of the file watcher
+.metro-health-check*
+
+# testing
+/coverage
+
+# Local measurement artifacts
+/artifacts/
+*.hprof
+
+# Generated BuildManifest asset (prepare step); scripts remain tracked
+android/app/src/main/assets/build-manifest.json
+
+# Ephemeral local JDK used only for CI-less verification (never commit)
+/.jdk/
+
+# Yarn
+.yarn/*
+!.yarn/patches
+!.yarn/plugins
+!.yarn/releases
+!.yarn/sdks
+!.yarn/versions

examples/benchmark-native/.prettierrc.js

@@ -0,0 +1,5 @@
+module.exports = {
+  arrowParens: 'avoid',
+  singleQuote: true,
+  trailingComma: 'all',
+};

examples/benchmark-native/.watchmanconfig

@@ -0,0 +1 @@
+{}