Unplugin provides a single Rollup-style plugin API that runs on Vite, Rollup, webpack, esbuild, Rspack, Rolldown, Farm, and Bun. Use these skills when implementing a new unplugin, integrating an existing one, or debugging hook/context behavior across bundlers.
The skill is based on unplugin v3.0.0, generated at 2026-01-30.
Core References
| Topic | Description | Reference |
|---|---|---|
| Overview | What unplugin is, supported bundlers, when to use | core-overview |
| Core API | createUnplugin, factory signature, bundler-specific creators | core-api |
| Hooks and context | Lifecycle hooks, filters, this.parse / emitFile / warn / error | core-hooks-and-context |
| Hook compatibility | Per-bundler support tables for hooks and context | core-hook-compatibility |
| Integration | Installing and registering in Vite, Rollup, webpack, etc. | core-integration |
Features
| Topic | Description | Reference |
|---|---|---|
| Filters | filter option for resolveId, transform, load (performance) | features-filters |
| Nested plugins | Returning an array of plugins from the factory | features-nested-plugins |
| Bundler-specific | meta.framework, escape hatches (vite/webpack/esbuild/…), createXxxPlugin | features-bundler-specific |
| Virtual modules | resolveId + load pattern; filter for load | features-virtual-modules |
| Parsing | setParseImpl, this.parse; when needed (esbuild, webpack, etc.) | features-parsing |
| Output and assets | emitFile (EmittedAsset only), writeBundle (timing only) | features-output-and-assets |
Best Practices
| Topic | Description | Reference |
|---|---|---|
| Conventions | unplugin- prefix, keyword, default + subpath exports | best-practices-conventions |
| Diagnostics | this.warn / this.error, UnpluginMessage shape | best-practices-diagnostics |
| Scaffolding | Templates (unplugin-starter), try online, prerequisites | best-practices-scaffolding |