# JoshuaKGoldberg/TypeStat

Converts JavaScript to TypeScript and TypeScript to better TypeScript. 🧫

Repository: https://github.com/JoshuaKGoldberg/TypeStat
Canonical: https://ross.abutalabs.com/products/typestat
Language: TypeScript
License: MIT
License Family: permissive
Topics: typescript, javascript, conversion, static-analysis, mutations
Last push: 2026-08-26T17:18:44+00:00

## Health v2 (maintenance only)
Score: 79/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 40, longevity 100
- inputs: {"age_days": 2846, "days_push": 7, "days_rel": 563, "gap_med": 1.5, "n_releases_24m": 17}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 2254, forks 46 (observed 2026-08-28T04:06:31.228619+00:00)

## What it is
TypeStat is a CLI utility that converts JavaScript files to TypeScript and improves type annotations in existing TypeScript code. It applies automated type mutations that only add or remove types without changing runtime behavior.

## Use cases
- convert a JavaScript codebase to TypeScript
- add types to files freshly converted from JavaScript
- fix noImplicitAny and noImplicitThis violations
- annotate missing nulls and undefineds for strictNullChecks
- automatically improve type annotations in existing TypeScript projects

## When to choose
- you are migrating a JavaScript project to TypeScript incrementally
- you want to enable stricter compiler flags like strictNullChecks without manually annotating everything
- you need automated, behavior-preserving type fixes across many files

## When to avoid
- you want a one-time full rewrite with runtime refactoring rather than type-only mutations
- your project is already fully and strictly typed
- you need a linter or formatter rather than a type mutation tool

## Facets
- artifact type: cli-tool
- maturity: active
- function: cli, parser, developer-tools, type-system
- domain: developer-tools, programming-languages
- platform: cli, cross-platform
- tags: typescript, javascript-to-typescript, code-mutation, static-analysis, codemod, type-annotation, strict-null-checks, no-implicit-any, automation, nodejs

## Member repositories
- JoshuaKGoldberg/TypeStat (main) score 79

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:06:31.228619+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 2026-08-30T02:43:45.850354+00:00, confidence not recorded.
  - readme: https://github.com/JoshuaKGoldberg/TypeStat (fetched 2026-08-28T04:06:31.228619+00:00, sha e9c9f55ed52d)
  - registry_npm: https://registry.npmjs.org/typestat (fetched 2026-08-29T10:23:53.035864+00:00, sha 6292d780401c)
- Data as of 2026-08-30T08:39:29.467469+00:00.