1.0.0 • Public • Published


Utility to build TypeScript projects that conform to a given set of conventions quickly and cleanly. Exports functions that wrap the TypeScript compiler and Rollup to build or watch one or more projects in one go, performing a single shared build (so that files from different projects aren't compiled twice).

Assumes your projects are set up like this:

  • TypeScript files in an src directory, will be compiled to dist/index.js (ES module), dist/index.cjs (CommonJS), and dist/index.d.ts (TypeScript) files.

  • Tests, if any, under test, will be compiled in-place to .js files, which are ES modules.

  • Doc comments prefixed with triple slash /// syntax will be converted to /** JSDoc comments in the output, so that TypeScript tooling picks them up.


  • build(main: string | readonly string[], options?: BuildOptions = {}) → Promise
    Build the package with main entry point main, or the set of packages with the given entry point files. Output files will be written to the dist directory one level up from the entry file. Any TypeScript files in a test directory one level up from main files will be built in-place.

  • watch(mains: readonly string[], extra?: readonly string[] = [], options?: BuildOptions = {})
    Build the given packages, along with an optional set of extra files, and keep rebuilding them every time an input file changes.

interface BuildOptions

Options passed to build or watch.

  • sourceMap?: boolean
    Generate sourcemap when generating bundle. defaults to false

  • tsOptions?: any
    Additional compiler options to pass to TypeScript.

  • bundleName?: string
    Base filename to use for the output bundle and declaration files. Defaults to "index".

  • expandLink?: fn(anchor: string) → string | null
    When given, this is used to convert anchor links in the /// comments to full URLs.

  • outputPlugin?: fn(root: string) → Plugin | Promise
    Adds a Rollup output plugin to use.

  • cjsOutputPlugin?: fn(root: string) → Plugin
    Adds an output plugin to use only for CommonJS bundles.

  • pureTopCalls?: boolean
    When set to true, add a /*@__PURE__*/ comment before top level function calls, so that tree shakers will consider them pure. Note that this can break your code if it makes top-level function calls that have side effects.

  • onRebuildStart?: fn(packages: readonly string[])
    Function to call when starting a rebuild via watch, passing the root directories of the packages that are being built. The default is to just log the base names of the directories.

  • onRebuildEnd?: fn(packages: readonly string[])
    Function to call when finishing a rebuild.


This is open source software released under an MIT license.

Development happens on GitHub. Use the bug tracker to report problems.




Package Sidebar


npm i @marijn/buildtool

Weekly Downloads






Unpacked Size

32.2 kB

Total Files


Last publish


  • marijn