unplugin by hairyf/skills

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