type-challenges
Solve puzzles using only TypeScript's type system
type-challenges is a collection of puzzles you solve with TypeScript types, not runtime code. Each challenge asks you to build a type, often your own version of a built-in utility type, and type tests check your answer. The challenges go from warm-up and easy to medium, hard and extreme, with about 190 in total.
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About type-challenges
The puzzles teach how the TypeScript type system really works, including generics and conditional types. Easy ones suit regular TypeScript users, while hard and extreme ones push experts.
You can solve each challenge in the TypeScript Playground with the project's plugin, and share answers on GitHub. It is free and open source under the MIT license.
On Breakpoint since 23 Oct 2026.