The inferred type of 'trpc' cannot be named without a reference

I'm getting the same error as this post: The inferred type of 'trpc' cannot be named without a reference ...

I have a monorepo setup with an

api

api

package (copied from https://github.com/t3-oss/create-t3-turbo/tree/main/packages/api) and a server + expo packages similarly copied from that monorepo.

Any ideas what I should be looking at to solve this issue?

The inferred type of 'trpc' cannot be named without a reference - tRPC