TypeScript 5.5 — The Features That Actually Matter for Production Code

TypeScript 5.5: The Features That Actually Matter for Production Code

TypeScript 5.5 shipped with a mix of headline features and subtle improvements that compound significantly in large codebases. After running it in production for months, here are the features that actually moved the needle for our team.

The Big One: Inferred Type Predicates

This sounds small but it's a massive DX improvement. TypeScript can now automatically infer type predicates from function implementations.

Before 5.5: The Verbose Manual Fix