Zod

Zod is a TypeScript-first schema validation library by Colin McDonnell (@colinhacks) for defining schemas, parsing untrusted data, and producing strongly typed validated results. It works with TypeScript and plain JavaScript in Node.js and modern browsers, has no external dependencies, and supports immutable schema composition, JSON Schema conversion, synchronous and asynchronous parsing, detailed ZodError issues, and safeParse result objects. Zod infers static types from schemas through utilities such as z.infer, z.input, and z.output; transforms can produce different input and output types. For hot validation paths, z.compile(schema) can create an ahead-of-time compiled fast path using new Function, while unsupported or asynchronous schemas use the regular parser.