yaup

1.8.0 verified Fri May 01 auth: no javascript

A minimal, unopinionated CLI wrapper around esbuild for building dual CJS/ESM packages with TypeScript declaration files. Current stable version is 1.8.0, maintained by egoist. It offers a simple config file (yaup.config.ts) with defineConfig, supporting multiple output formats (esm, cjs, dts). Unlike opinionated alternatives like tsup or rollup, yaup stays close to raw esbuild, giving users flexible configuration with minimal API surface. Release cadence is irregular; the author is not accepting new features unless critical.

Common errors

error Error: Cannot find module 'esbuild' ↓

cause esbuild is a peer dependency not installed automatically

fix

npm install esbuild --save-dev

error Error: Config file not found: yaup.config.ts ↓

cause Config file must be in the root of the project or specified with --config

fix

Place yaup.config.ts in project root or use yaup --config /path/to/config

error TypeError: defineConfig is not a function ↓

cause Using CommonJS require() instead of ESM import

fix

Change to import { defineConfig } from 'yaup' and ensure package.json has "type": "module"

Warnings

breaking Dropped Node.js <12 support in v1.6.0 ↓

fix Upgrade yaup to >=1.6.0 or use Node.js >=12

deprecated format: 'types' renamed to 'dts' in v1.3.0 ↓

fix Use 'dts' instead of 'types' in output format

gotcha Config file must be named yaup.config.ts or yaup.config.js; other names are ignored ↓

fix Rename config file to yaup.config.ts or yaup.config.js

gotcha The input path must be relative to config file location, not cwd ↓

fix Use paths relative to the config file or absolute paths

Install

npm install yaup

yarn add yaup

pnpm add yaup

Imports

defineConfig

wrong

const defineConfig = require('yaup').defineConfig

correct

import { defineConfig } from 'yaup'

yaup is ESM-only, use import syntax

startDevServer

wrong

const startDevServer = require('yaup').startDevServer

correct

import { startDevServer } from 'yaup'

Export for development server, available since v1.5.0

build

wrong

const yaup = require('yaup'); yaup.build()

correct

import { build } from 'yaup'

build is a named export, not a method on default

Quickstart

Basic config to build dual CJS/ESM and Type declarations from a single entry

// yaup.config.ts
import { defineConfig } from 'yaup'

export default defineConfig({
  input: './src/index.ts',
  output: [
    { format: 'esm', dir: 'dist/esm' },
    { format: 'cjs', dir: 'dist/cjs' },
    { format: 'dts', dir: 'dist/types' },
  ],
})