## [1.0.0-beta.53] - 2025-12-03

💥 Breaking Changes
- Drop `i686-pc-windows-msvc` target support

🚀 Chunk Merging Optimization
- Rolldown now automatically merges shared chunks when entries import each other (when `preserveEntrySignature` is not `strict`)
```shell
Before:
entry.js   → imports → shared.js (common chunk)
entry2.js  → imports → shared.js
Output: 3 chunks (entry.js, entry2.js, shared.js)

After:
entry.js   → contains shared code
entry2.js  → imports → entry.js
Output: 2 chunks (entry.js, entry2.js)
```

### 💥 BREAKING CHANGES

- drop `i686-pc-windows-msvc` target support (#7230) by @sapphi-red

### 🚀 Features

- rolldown_plugin_vite_manifest: pass normalized options to `isLegacy` callback (#7321) by @shulaoda
- plugin/vite-resolve: add `disableCache` option (#6763) by @sapphi-red
- rolldown: export `createTokioRuntime` for tsdown (#7264) by @shulaoda
- rolldown_plugin_vite_html: sync `moduleSideEffects` for already loaded modules (#7254) by @shulaoda
- rolldown_plugin_vite_html: load module scripts with side effects to prevent tree-shaking (#7244) by @shulaoda
- rolldown_plugin_vite_css_post: implement `cssScopeTo` for scoped CSS tree-shaking (#7240) by @shulaoda

### 🐛 Bug Fixes

- export default class decl __name runtime insertion (#7316) by @IWANABETHATGUY
- chunk side effects calculation (#7273) by @IWANABETHATGUY
- node: `output.generateCode.preset: 'es2015'` should set `output.generateCode.symbols: true` by default (#7314) by @sapphi-red
- skip name helper for classes with static name property (#7312) by @IWANABETHATGUY
- preserve chunk imports relationship after chunk merging (#7303) by @shulaoda
- dev: make `register_modules` async (#7289) by @hyf0
- preserve computed property in object destructuring (#7288) by @IWANABETHATGUY
- support dynamic imports with shared dependencies (#7261) by @IWANABETHATGUY
- call `defer_sync_scan_data` in non-incremental build mode (#7255) by @shulaoda
- optimize chunk merging for shared entry points (#7194) by @IWANABETHATGUY
- add indentation for UMD format output (#7263) by @IWANABETHATGUY
- rolldown_plugin_vite_css_post: pass options to `isLegacy` callback for proper legacy detection (#7260) by @shulaoda
- rolldown_plugin_vite_css_post: also detect `?inline=true` query for inlined CSS (#7245) by @shulaoda
- rolldown_plugin_vite_css_post: distinguish empty CSS from no CSS (#7241) by @shulaoda
- add Windows support for t-run command (#7242) by @IWANABETHATGUY
- cjs: prevent duplicate require declarations for external modules with preserveModules (#7234) by @logaretm
- rolldown_plugin_vite_resolve: resolve from root for virtual modules (#7236) by @sapphi-red
- include entry level external modules in chunk exports (#7218) by @IWANABETHATGUY

### 🚜 Refactor

- dev: make `removeClient` async (#7313) by @hyf0
- move chunk merging code out of code_splitting.rs (#7285) by @IWANABETHATGUY
- extract common function util for chunk merging (#7271) by @IWANABETHATGUY
- use iterative method to merge chunks (#7256) by @IWANABETHATGUY
- use concat_string! instead of string replace for generating chunk level exports (#7247) by @IWANABETHATGUY

### 📚 Documentation

- add warning to experimental.resolveNewUrlToAsset about JS/TS files (#7300) by @Copilot
- add sequential hook execution difference in plugin-api.md (#7308) by @Copilot
- add migration example from onwarn to onLog (#7299) by @Copilot
- add migration example for manualChunks to advancedChunks (#7298) by @Copilot
- deps: bump vitepress to fix build (#7307) by @sapphi-red
- examples & text for experimental.resolveNewUrlToAsset (#7259) by @TheAlexLichter

### ⚡ Performance

- rolldown_plugin_vite_css_post: lazily load `cssScopeTo` from JS module options (#7253) by @shulaoda
- rolldown_plugin_vite_css_post: avoid unnecessary string clones in `resolve_asset_urls_in_css` (#7250) by @shulaoda

### 🧪 Testing

- generate relative path like name in advanced chunks (#7267) by @IWANABETHATGUY
- add test case for preserveEntrySignatures with re-exports (#7279) by @IWANABETHATGUY
- add test262 integration tests (#7196) by @sapphi-red

### ⚙️ Miscellaneous Tasks

- deps: update dependency rolldown-plugin-dts to v0.18.1 (#7304) by @renovate[bot]
- enable tracing feature for napi (#7322) by @sapphi-red
- deps: update napi (#7320) by @renovate[bot]
- deps: update oxc (#7318) by @renovate[bot]
- deps: update napi (#7317) by @renovate[bot]
- deps: update oxc to v0.100.0 (#7301) by @renovate[bot]
- deps: downgrade pnpm to 10.23.0 to fix Netlify build (#7306) by @shulaoda
- add `trustPolicyExclude` for chokidar and semver (#7302) by @sapphi-red
- update pnpm lockfile (#7291) by @IWANABETHATGUY
- deps: update npm packages (#7272) by @renovate[bot]
- deps: update rust crates (#7270) by @renovate[bot]
- deps: update oxc (#7262) by @renovate[bot]
- deps: update github-actions (#7269) by @renovate[bot]
- deps: update dependency dprint-typescript to v0.95.13 (#7268) by @renovate[bot]
- deps: update `html5gum` to 0.8.1 (#7265) by @shulaoda
- rolldown: remove unused `getModuleOptions` from `PluginContext` (#7266) by @shulaoda
- remove unnecessary justfile ignore (#7243) by @IWANABETHATGUY
- deps: update oxc apps (#7238) by @renovate[bot]
- add `nul` to workaround https://github.com/anthropics/claude-c… (#7237) by @IWANABETHATGUY
- deps: update dependency valibot to v1.2.0 [security] (#7231) by @renovate[bot]
- deps: update crate-ci/typos action to v1.40.0 (#7232) by @renovate[bot]

### ❤️ New Contributors

* @logaretm made their first contribution in [#7234](#7234)

Co-authored-by: shulaoda <[email protected]>