I have code like:

export default foo;

but for some reason, tsup compiles this as:

export { foo as default }

I have confirmed that tsc does not compile this way, so it's something on tsup's side.

here's my tsup.config:

import { defineConfig } from 'tsup';

const commonOptions = {
  entry: ['src/index.ts', 'src/debug.ts'],
  splitting: false,
  sourcemap: true,
  clean: true,
  minify: true,
};

export default defineConfig(() => [
  {
    ...commonOptions,
    format: 'esm',
    // outExtension: () => ({ js: '.mjs' }),
    dts: true,
    clean: true,
  },
]);

this is breaking auto-import of packages for me, so I'd rather just use the normal export default which fixes the problem.