This is a template project that has auth set up using NextAuth (Auth.js) & tRPC set up for data fetching. A lot of the little useful hacks and tools set up here are also swiped from the create-t3-app template: trpc bits, env validation (with explainer comments), getBaseUrl(), and the eslint & prettier configs.
Currently, tRPC does not have an official method for use with the App Directory. This implementation uses it via the fetch adapter, as app dir Routes use the Request & Response API.
No Prisma/Kysely/Drizzle/OtherDB?
There is no database adapter/layer configured here because that is not something this template is meant to have an opinion on.