@runtyped/type

TypeScript types disappear at runtime. Runtyped changes that, preserving types at runtime via a compiler plugin.

import { is, cast, validate, serialize, typeOf, toJsonSchema } from '@runtyped/type';

interface User {
  id: number;
  registered: Date;
  username: string;
}

// Deserialize JSON to typed objects (strings become Dates, etc.)
const user = cast<User>({
  id: 1,
  registered: '2024-01-15T10:30:00Z',
  username: 'peter'
});
user.registered instanceof Date; // true

// Validate data against type
validate<User>({ id: 'not a number' });
// [{ path: 'id', message: 'Not a number' }]

// Serialize to JSON-safe output
serialize<User>(user);
// { id: 1, registered: '2024-01-15T10:30:00.000Z', username: 'peter' }

// Full runtime type reflection
const type = typeOf<User>();

// Convert type to JSON Schema
const schema = toJsonSchema<User>();

Use with @runtyped/type-compiler. Check the documentation at https://github.com/runtyped/runtyped.