# piotrwitek/utility-types

Collection of utility types, complementing TypeScript built-in mapped types and aliases (think "lodash" for static types).

Repository: https://github.com/piotrwitek/utility-types
Canonical: https://ross.abutalabs.com/products/utility-types
Language: TypeScript
License: MIT
License Family: permissive
Topics: typescript, utility-types, utilities, static-typing, mapped-types
Last push: 2026-05-09T10:55:38+00:00

## Health v2 (maintenance only)
Score: 59/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 81, release rhythm 8, longevity 100
- inputs: {"age_days": 3550, "days_push": 116, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 5763, forks 235 (observed 2026-08-28T04:09:29.349571+00:00)

## What it is
A TypeScript library providing a collection of utility types (like lodash for static types) that complement TypeScript's built-in mapped types and aliases, including Flow-compatible utility types to ease migration from Flow to TypeScript.

## Use cases
- get common utility types for TypeScript projects without copying them between projects
- migrate a Flow codebase to TypeScript using Flow-compatible utility types
- pick, omit, or transform object types at the type level
- write type-level tests for TypeScript type correctness
- avoid third-party dependencies and runtime cost for type utilities

## When to choose
- You want a well-tested, dependency-free set of idiomatic TypeScript utility types
- You're migrating from Flow to TypeScript and need Flow-compatible type utilities
- You want type-level-only helpers with zero runtime cost

## When to avoid
- Your project uses JavaScript without static typing
- TypeScript's built-in utility types already cover your needs
- You need runtime type validation rather than compile-time types

## Facets
- artifact type: library
- maturity: stable
- function: type-system, developer-tools
- domain: programming-languages, developer-tools
- platform: cross-platform
- tags: typescript, static-typing, mapped-types, type-level-programming, flow-compatibility, zero-runtime, nodejs

## Member repositories
- piotrwitek/utility-types (main) score 59

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:09:29.349571+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T17:52:57.177883+00:00, confidence not recorded.
  - readme: https://github.com/piotrwitek/utility-types (fetched 2026-08-28T04:09:29.349571+00:00, sha 28d4025bc005)
  - registry_npm: https://registry.npmjs.org/utility-types (fetched 2026-08-29T08:48:38.605951+00:00, sha ee48148a62b3)
- Data as of 2026-08-30T08:39:29.467469+00:00.