tsdown

Bundle TypeScript libraries with Rolldown and Oxc, generating typings and exports.

Updated Jan 11, 2026
One-click install
npx skills add https://github.com/UmmItKin/ummit.dev --skill tsdown-ummitkin
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: tsdown
Source: https://github.com/UmmItKin/ummit.dev/tree/main/.agents/skills/tsdown
Command: npx skills add https://github.com/UmmItKin/ummit.dev --skill tsdown-ummitkin

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve?

tsdown bundles TypeScript libraries quickly and reliably, providing a modern bundling workflow powered by Rolldown and Oxc, including typings generation and export maps.

Core Features & Use Cases

  • Blazing-fast builds for TypeScript libraries using Rolldown and Oxc.
  • Automatic .d.ts generation and support for package exports.
  • Flexible entry-point configuration and multi-format output (ESM/CJS).
  • Use Case: Publish a TS library to npm with ready-to-publish bundles, typings, and exports.

Quick Start

Create a tsdown.config.ts with your library entry and export settings, then run tsdown to build and generate typings and exports.

Frequently Asked Questions about tsdown

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
What is the best way to bundle a TypeScript library for npm publishing?

To bundle TypeScript libraries, create a tsdown.config.ts file defining your entry points and export settings, then run tsdown to execute the build and generate typings.

How do I generate .d.ts type declarations when building TypeScript libraries?

Generating .d.ts type declarations when building TypeScript libraries is automatic with tsdown, which configures dts options to produce typings alongside multi-format ESM and CJS output.

Can I output both ESM and CJS formats from a single TypeScript library build?

Outputting both ESM and CJS formats from a single TypeScript library build is supported by tsdown through its multi-output build configuration and flexible entry-point setup.

Why use Rolldown and Oxc for TypeScript build tooling instead of other bundlers?

Using Rolldown and Oxc for TypeScript build tooling provides blazing-fast build speeds for libraries, offering a modern alternative to slower bundlers while handling exports and typings automatically.

How do I configure package exports for a multi-format TypeScript library?

Configuring package exports for a multi-format TypeScript library is managed by tsdown, which generates export maps automatically based on your defined entry points and output formats.