Workspace

Workspace mode enables building multiple packages in a monorepo from a single tsdown invocation. The root configuration is automatically inherited by each sub-package, with per-package overrides supported when needed.

Quick Start

tsdown --workspace

Or in config:

tsdown.config.ts

import { defineConfig } from 'tsdown'

export default defineConfig({
  workspace: true,
  entry: ['src/index.ts'],
})

Given:

my-monorepo/
|-- package.json
|-- tsdown.config.ts      # workspace: true, entry: ['packages/*']
|-- packages/
|   |-- foo/
|   |   |-- package.json
|   |   |-- src/index.ts
|   |-- bar/
|       |-- package.json
|       |-- src/index.ts

Both foo and bar are built using the root config, each outputting to its own dist/.

Package Discovery

Auto Mode

workspace: true scans for **/package.json (excluding the root) and treats each matching file's parent directory as a workspace package:

export default defineConfig({ workspace: true })

Default exclusions:

• **/node_modules/**
• **/dist/**
• **/test?(s)/**
• **/t?(e)mp/**

Customize exclusions:

export default defineConfig({
  workspace: {
    include: 'auto',
    exclude: ['**/node_modules/**', '**/dist/**', '**/vendor/**'],
  },
})

Explicit Mode

When sub-packages don't all have package.json or you want to restrict which directories participate:

// Glob pattern
export default defineConfig({ workspace: 'packages/*' })

// Multiple paths
export default defineConfig({ workspace: ['packages/foo', 'packages/bar'] })

// Object form
export default defineConfig({
  workspace: {
    include: 'packages/*',
  },
})

In explicit mode, directories are matched by glob. A package.json is not required for discovery.

Filtering Packages

--filter (or -F) restricts which packages are built, matched against the package name or directory:

tsdown -W -F my-package
tsdown -W -F /packages\/utils/

Configuration Inheritance

The root config is merged into each sub-package's config: sub-package values override root values, and any option not set by the sub-package falls back to the root.

tsdown.config.ts

export default defineConfig({
  workspace: true,
  entry: ['src/index.ts'],
  format: ['esm', 'cjs'],
  clean: true,
  dts: true,
})

packages/bar/tsdown.config.ts

// Sub-package:
export default defineConfig({
  // override entry
  entry: ['index.ts'],
  // format, clean, dts inherited from root
})

All path-based options (entry, outDir, etc.) are resolved relative to each sub-package's directory.

Per-Package Configuration

Sub-packages can define their own configuration through a config file in the sub-package directory or the tsdown field in their package.json. See Config File for supported formats and loaders.

Accessing Root Config

A sub-package config function receives the resolved root config:

packages/bar/tsdown.config.ts

import { defineConfig } from 'tsdown'

export default defineConfig((_inlineConfig, { rootConfig }) => ({
  entry: rootConfig.entry ?? ['index.ts'],
}))

Disabling Per-Package Configs

When all sub-packages share the same configuration, skip per-package config loading:

export default defineConfig({
  workspace: {
    config: false,
  },
})

With config: false, sub-package tsdown.config.* files and the package.json#tsdown field are ignored. The root config applies as-is to every sub-package.