tsdown

tsdown — next-generation bundler for TS libraries, powered by rolldown.

Build ToolsSimple

Stack Components

Bundlertsdown 0.x

Baserolldown

Why

Rust-powered rollup, faster than rollup, unbuild-compatible config. Vite 5 builds 10-20x faster than Webpack (esbuild + Rollup core).

Turborepo and Nx cut monorepo CI times by 60-80% via remote caching and task parallelization.

When

Use for TS library builds needing speed. Avoid for app bundling.

How

1. npm install tsdown 2. Create tsdown.config.ts 3. npx tsdown 4. Publish 5. Add environment configuration — cp .env.example .env && edit values 6. Run tests — npm test or pnpm test to verify setup 7. Deploy — git push to trigger CI/CD or manual deploy

Example

export default { entry: ['src/index.ts'], format: ['esm', 'cjs'], dts: true, };

Common Problems

⚠rolldown compat — check rollup plugin support
⚠Early stage — API may change
⚠Configuration drift between environments — use infrastructure-as-code (Terraform/Pulumi) to keep dev/staging/prod identical

Best Practices

✓Use clean option for fresh builds
✓Leverage persistent cache
✓Set up health checks and graceful shutdown — handle SIGTERM to drain in-flight requests before exit

FAQ

What is tsdown and what projects is it for?

tsdown — next-generation bundler for TS libraries, powered by rolldown. It pairs layered technologies for end-to-end type safety and out-of-the-box deploys, fitting everything from MVPs to production SaaS.

How do I spin up a working demo with tsdown in 10 minutes?

Two steps: (1) npm install tsdown; (2) Create tsdown.config.ts. Get the local dev server running, then wire one real data source to verify the end-to-end loop.

What is the most common pitfall with tsdown and how do I avoid it?

The most common pitfall is: rolldown compat — check rollup plugin support. Avoid it by adding the matching checklist to your PR template and running type-check + lint + unit tests in CI — three gates before merge.

What are the best practices for tsdown?

Best practices for tsdown include: Use clean option for fresh builds; Leverage persistent cache; Set up health checks and graceful shutdown — handle SIGTERM to drain in-flight requests before exit. The first one — "Use clean option for fresh builds" — should be set up at project init to avoid costly rework later.

When should I NOT choose tsdown?

Pick something else in three cases: (1) the team has zero experience with the core framework and the deadline is tight (learning-curve risk); (2) it's a pure content/marketing site (Astro is lighter); (3) you need very high throughput (>10k RPS) or strict-consistency microservices (Go/Rust). tsdown shines for mid-to-high complexity full-stack and API work — don't over-engineer simple static pages with it.