tsup multi entrypoint

tsup.config.ts

import fs from 'fs';
import path from 'path';

import { defineConfig } from 'tsup';

// INFO: This is the only place you need to update when adding new entry folders
const entryFolders = ['primitives', 'ui'];

function getAllFilesInDirectory(dirPath: string): string[] {
  return fs.readdirSync(dirPath).reduce<string[]>((allFiles, file) => {
    const fullPath = path.join(dirPath, file);
    if (fs.statSync(fullPath).isDirectory()) {
      return allFiles.concat(getAllFilesInDirectory(fullPath));
    } else {
      return allFiles.concat('./' + fullPath);
    }
  }, []);
}

export default defineConfig({
  entry: entryFolders
    .map((folder) => getAllFilesInDirectory(`./src/${folder}`))
    .flat(),
  external: ['@noodle/styled-system'],
  format: ['esm'],
  splitting: true,
  sourcemap: true,
  clean: true,
  dts: true,
  outDir: 'dist',
  onSuccess: async () => {
    const packageJsonPath = './package.json';
    const packageJson = JSON.parse(fs.readFileSync(packageJsonPath, 'utf-8'));
    const distFiles = getAllFilesInDirectory('./dist').filter((file) =>
      file.endsWith('.js'),
    );

    packageJson.exports = distFiles.reduce<
      Record<string, { import: string; types: string }>
    >((exports, file) => {
      const key = file.replace('dist/', '').replace('.js', '');
      exports[key] = { import: file, types: file.replace('.js', '.d.ts') };
      return exports;
    }, {});

    fs.writeFileSync(packageJsonPath, JSON.stringify(packageJson, null, 2));
  },
});

you can just do entry: ['./src/**/*.ts'] and specify your exports in package.json