Next build can't resolve monorepo aliases. It's killing me

Question

I am building a simple nextjs frontend with an express backend. I can run them both together in dev mode perfectly. But when I try to 'next build' the front package, there seem to be problems that I am assuming are released to the monorepo. But I'm not sure. This is killing me and I've been stuck on this for over a week!!! I would appreciate any help from a monorepo genius!

This is the repo. The simple repro path is travel into the front package, pnpm install, and then pnpm build.

You can see that it has problems compiling thought the dev servers of the server and the front both work so well.

https://github.com/dsmurl/an-express-next