A comprehensive collection of highly-optimized TypeScript type utilities for building type-safe applications
npm install devtypesA comprehensive collection of more than 150 high-performance TypeScript type utilities focused on type safety and developer experience.
- Zero Runtime Overhead - Pure type definitions
- Type Safety - Advanced constraint utilities
- Modular Design - Import only what you need
- Rich Toolset - From basic to advanced type operations
- IntelliSense Optimized - Great IDE support
``bash`
npm install devtypes
Read the full devtypes Documentation for detailed usage instructions, examples, and API references.
`ts
import type { Merge } from 'devtypes/merge';
import type { RequireExactlyOne } from 'devtypes/constraint';
type UserBase = { id: number; name: string; email?: string };
type UserAuth = { email: string; password: string };
// Merge types (smart conflict resolution)
type User = Merge< UserBase, UserAuth >;
// { id: number; name: string; email: string; password: string }
// Require exactly one field
type LoginCredentials = RequireExactlyOne<
{ email?: string; phone?: string; username?: string; },
'email' | 'phone' | 'username'
>;
`
`ts
import type { DeepPartial, DeepRequired } from 'devtypes/transform';
interface Config {
server: {
port: number;
host: string;
ssl?: {
cert: string;
key: string;
};
};
database: {
url: string;
timeout?: number;
};
}
// Make everything optional
type PartialConfig = DeepPartial< Config >;
// Make everything required
type FullConfig = DeepRequired< Config >;
`
| Module | Purpose |
|--------|---------|
| assert | Assertion utilities for compile-time checks |
| class | Class-specific utilities: methods, properties, constructors |
| condition | Conditional type utilities (If and Equals) |
| constraint | Property requirement constraints and validation |
| functional | Functional type utilities: curry, compose, promisify |
| guard | Type guard utilities for runtime type checking |
| list | List-like structures (arrays, sets, maps, records, iterables) |
| merge | (Deep) merging and intersection of types |
| object | Object type manipulation and property utilities |
| primitive | Primitive type utilities and literal handling |
| transform | (Deep) transformations for objects, arrays, and nested structures |
| tuple | Tuple-specific utilities and manipulations |
| union | Union type utilities: exclusion, extraction, conversion |
| util | Generic utility types: branding, boxing, casting, simplification |
Import from specific modules for best IDE performance:
`ts
// Good - direct import
import type { Brand } from 'devtypes/util';
import type { MethodNames } from 'devtypes/class';
// Avoid - star imports slow down IntelliSense
import * as Types from 'devtypes';
``
Contributions are welcome! Please feel free to submit a pull request.
Copyright 2025–2026 Paul Köhler (komed3).
Distributed under the MIT license.