tsdown

Name: tsdown
Availability: InStock
Author: shana-ae

Bundle TypeScript libraries with Rolldown and Oxc into ESM and CJS formats.

2|Updated Jan 28, 2026

Search Tags:#typescript #migration #library #bundling #rolldown #tsdown #oxc

Ready to run

npx skills add https://github.com/Shana-AE/.shanaae-configs --skill tsdown-shana-ae

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: tsdown
Source: https://github.com/Shana-AE/.shanaae-configs/tree/main/ai/skills/vendor/tsdown
Command: npx skills add https://github.com/Shana-AE/.shanaae-configs --skill tsdown-shana-ae

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve?

tsdown speeds up bundling TypeScript libraries by providing a fast, Rolldown-based pipeline that also auto-generates declaration files and helps migrate from tsup, improving build reproducibility and distribution readiness.

Core Features & Use Cases

Fast TypeScript library bundling with ESM-first output and optional additional formats
Automatic TypeScript declaration file generation and optional sourcemaps
Migration-friendly tool that supports dual-config builds, exports automation, and plugin compatibility
Use cases include publishing library packages, building dual-format libraries, and prepping packages for distribution

Quick Start

Install and run tsdown on your library project to start bundling with declarations generation.

Frequently Asked Questions about tsdown

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

FAQPage Schema

How do I bundle TypeScript libraries with dual ESM and CJS outputs?▼

You can bundle TypeScript libraries with dual ESM and CJS outputs using tsdown, which provides ESM-first output with optional additional formats and automated package-exports management. It leverages Rolldown and Oxc for blazing-fast builds.

What is the best way to migrate a TypeScript bundling config from tsup?▼

Migrating from tsup is supported through tsdown's migration-friendly tooling, which provides automated migration guidance and dual-config build compatibility. This allows you to transition your library builds to the faster Rolldown pipeline smoothly.

Does tsdown support plugin compatibility for custom library builds?▼

Yes, tsdown supports plugin compatibility to customize your TypeScript library builds. This allows you to extend the Rolldown-based bundling pipeline while maintaining fast build speeds and automated declaration file generation.

Can I generate TypeScript declaration files with sourcemaps when bundling libraries?▼

Yes, you can generate TypeScript declaration files with optional sourcemaps when bundling libraries using tsdown. It automatically produces these declarations alongside ESM-first output to ensure your packages are fully ready for distribution.