I have this setup and integrated for Node/Bun -
This is an example of a unit test of an API route on a fully isolated WASM backed Postgres - very few lines of code, and all your API unit tests can run fully in parallel without any shared state: https://github.com/ben-pr-p/bprp-react-router-starter/blob/m...
This is all of the code needed to use Postgres in prod and PGLite in test/dev: https://github.com/ben-pr-p/bprp-react-router-starter/blob/m...