Arktype is a TypeScript runtime validation library and schema orchestrator. It synchronizes TypeScript types with runtime data validation, allowing users to define type-safe schemas that ensure unknown data adheres to specific structures during application execution.
The project distinguishes itself by using set-theory type analysis to determine intersections and subtype compatibility, alongside JIT-compiled validation functions for optimized performance. It supports advanced type modeling through branded type constraints, recursive alias resolution, and the ability to generate runtime validation logic directly from TypeScript type definitions.
The system covers a broad surface of data validation and transformation, including complex structure validation for objects, tuples, and class instances. It provides data transformation pipelines that morph and pipe values through a sequence of validations, as well as bidirectional mapping between internal representations and standard JSON Schema formats.
Additional capabilities include environment variable validation, custom validation error serialization, and programmatic type introspection for analyzing relationships between different schemas.