This repo demonstrates an issue with a dual-package dependency (dep) in a multi-project build, where one project (app) has ESNext module and Bundler module resolution, while another (lib) has NodeNext module and module resolution.

Despite everything being set up to use ESM, somehow TypeScript resolves the CJS types when transitively importing the dual package.

$ npm install

$ npm run build

> build
> tsc --build

app/src/index.ts:4:7 - error TS2322: Type '"CJS"' is not assignable to type '"ESM"'.

4 const test: ModuleType = moduleType;
        ~~~~


Found 1 error.