majiayu000 TypeScript Library Development
Patterns for authoring high-quality TypeScript libraries, extracted from studying unocss, shiki, unplugin, vite, vitest, vueuse, zod, trpc, drizzle-orm, and more.
When to Use
- Starting a new TypeScript library (single or monorepo)
- Setting up package.json exports for dual CJS/ESM
- Configuring tsconfig for library development
- Choosing build tools (tsdown, unbuild)
- Designing type-safe APIs (builder, factory, plugin patterns)
- Writing advanced TypeScript types
- Setting up vitest for library testing
- Configuring release workflow and CI
For Nuxt module development: use nuxt-modules skill
Quick Reference
| Working on... | Load file |
|---|---|
| New project setup | references/project-setup.md |
| Package exports | references/package-exports.md |
| tsconfig options | references/typescript-config.md |
| Build configuration | references/build-tooling.md |
| ESLint config | references/eslint-config.md |
| API design patterns | references/api-design.md |
| Type inference tricks | references/type-patterns.md |
| Testing setup | references/testing.md |
| Release workflow | references/release.md |
| CI/CD setup | references/ci-workflows.md |
Loading Files
Consider loading these reference files based on your task:
- references/project-setup.md - if starting a new TypeScript library project
- references/package-exports.md - if configuring package.json exports or dual CJS/ESM
- references/typescript-config.md - if setting up or modifying tsconfig.json
- references/build-tooling.md - if configuring tsdown, unbuild, or build scripts
- references/eslint-config.md - if setting up ESLint for library development
- references/api-design.md - if designing public APIs, builder patterns, or plugin systems
- references/type-patterns.md - if working with advanced TypeScript types or type inference
- references/testing.md - if setting up vitest or writing tests for library code
- references/release.md - if configuring release workflow or versioning
- references/ci-workflows.md - if setting up GitHub Actions or CI/CD pipelines
DO NOT load all files at once. Load only what's relevant to your current task.
Key Principles
- ESM-first:
"type": "module"with.mjsoutputs - Dual format: always support both CJS and ESM consumers
moduleResolution: "Bundler"for modern TypeScript- tsdown for most builds, unbuild for complex cases
- Smart defaults: detect environment, don't force config
- Tree-shakeable: lazy getters, proper
sideEffects: false
Token efficiency: Main skill ~300 tokens, each reference ~800-1200 tokens