Yup

This library provides a concise and expressive interface for building schemas that handle runtime value parsing and validation. Whether you need to transform raw input into a specific format or assert the shape of an existing object, it offers a robust set of tools to model complex, interdependent data requirements.

Key capabilities include:

• Powerful TypeScript Integration: Automatically infer static types from your schemas to ensure end-to-end type safety.
• Built-in Async Validation: Seamlessly handle both client-side and server-side validation logic.
• Extensible Architecture: Easily add custom type-safe methods and validation rules to fit your specific project needs.
• Rich Error Reporting: Receive detailed feedback on validation failures, making debugging and user-facing error messages straightforward.

By separating parsing transforms from validation tests, the library allows for highly flexible data handling. You can coerce inputs into correct types, strip unknown properties, or define complex conditional logic using references to other fields. It is designed to be immutable, ensuring that schema reuse is safe and predictable across your application.