Most TypeScript projects barely scratch the surface of what the type system can enforce at compile time. This post walks through four real-world patterns using conditional types, mapped types, and the infer keyword that eliminate entire categories of runtime bugs.
TypeScript will happily let you pass a UserId where you meant OrderId, and the bug slips into production. Branded types add nominal typing with zero runtime cost, catching mismatched IDs, raw strings, and domain violations before they hit your database.