type-guards

🛡 Comprehensive collection of type guards for JavaScript and TypeScript; Inspired by Elixir

Build small guards. Compose them. A lightweight, zero-dependency toolkit for building reusable TypeScript type guards that compose, refine, and preserve natural narrowing. Runtime-safe 🛡️, composable 🧩, and ergonomic ✨.

This library offers guards for common types, and methods to generate type guards for specific types quickly. Safely handle unpredictable unknown types with ease.

Runtime duck type checking utilities for TypeScript.

A comprehensive collection of type-guards, type assertions and related utils

Type safe, composable type guards for TypeScript

A lightweight TypeScript library providing type-safe assertions, type guards, and error handling utilities.

Combine user-defined type guards / type predicates as unions and intersections.

Bulletproof type guards in TypeScript.

A focused collection of TypeScript utilities for modern web development. Zero dependencies. Tree-shakeable.

Runtime type assertions that return

A collection of JS helper functions to be used in conditional logic within projects.

A utility for creating type-safe user-defined type guard for TypeScript

Standalone implementation of the entire `Math` namespace (and more!), compatible with any JS runtime. Zero dependencies.

Just another portable platform-agnostic package of high-performance type predicates. 🤪

Typechecking with ease.

TypeScript library with additional utility types and predicators generation

eslint-plugin-is-kit identifies ambiguous, redundant, or weakly typed predicates and suggests is-kit predicates when they improve intent or type narrowing.

Generate runtime type guards directly from your TypeScript types — no schemas, no decorators, no runtime parser.

TypeScript notes: structural typing, inference and annotations, the type zoo, aliases and interfaces, classes and functions, assertions, type guards, intersections and generics.