How to Learn Type-Level Programming?

• Do Type challenges. It's a large, open-source list of challenges you need to solve using only types. It comes with tests and community solutions.
• https://type-level-typescript.com/ → A thorough guide to practical programming with types by Gabriel Vergnaud (author of ts-pattern).
• Study the source code of libraries that do cool things with types, e.g.:
  • DrizzleORM
  • zod
  • ts-pattern
  • …
• Check out Walk That Type. A (work-in-progress) tool I working on that lets you paste or write any type, then step through it while explaining what happens at each step!
• Write a lot of types!