Directory

Open Source Packages

Libraries, frameworks, tools, and SDKs used by the apps in this directory — scored the same way as the apps themselves.

5929 packages

All Packages

97Health
Tool npm

TypeScript

A strongly typed superset of JavaScript that compiles to clean, portable JavaScript.

111,050
Apache 2.0
Used by 500
95Health
Tool npm

ESLint

The pluggable JavaScript and TypeScript linter that finds and fixes code problems through a fully customizable, plugin-based rule engine.

27,504
MIT
Used by 368
91Health
Tool npm

prettier

An opinionated code formatter that enforces consistent style across every language your project speaks.

52,263
MIT
Used by 310
94Health
Tool npm

typescript-eslint

The official meta-package bundling the TypeScript ESLint parser, plugin, and rule presets behind a single typed config() helper.

16,391
MIT
Used by 260
86Health
Tool npm

tsx

A drop-in replacement for the node CLI that runs TypeScript and ESM files instantly, powered by esbuild.

12,141
MIT
Used by 177
82Health
Tool npm

esbuild

An extremely fast JavaScript and CSS bundler and minifier written in Go.

40,058
MIT
Used by 139
62Health
Tool npm

eslint-plugin-react

React-specific linting rules for ESLint that catch JSX bugs, enforce Hooks conventions, and keep prop usage consistent.

9,292
MIT
Used by 122
82Health
Tool npm

eslint-plugin-import

ESLint rules that validate ES module import/export syntax and catch broken paths before they hit your build.

5,944
MIT
Used by 116
97Health
Tool npm

webpack

A static module bundler that builds a dependency graph of your project's modules and packages them into optimized browser bundles

65,948
MIT
Used by 90
95Health
Tool npm

Storybook

The industry-standard workshop for building, documenting, and testing UI components in isolation, across every major frontend framework.

91,053
MIT
Used by 83
91Health
Tool PyPI

Uvicorn

A lightning-fast ASGI server for Python, built on uvloop and httptools.

10,963
BSD 3
Used by 81
90Health
Tool npm

Oxlint

Rust-based JavaScript/TypeScript linter that runs 50-100x faster than ESLint, with zero configuration required.

22,741
MIT
Used by 70
72Health
Tool npm

css-loader

Resolves CSS @import and url() like JavaScript imports so webpack can bundle stylesheets and their assets.

4,320
MIT
Used by 65
90Health
Tool npm

SWC

Rust-based JavaScript/TypeScript compiler, a drop-in super-fast alternative to Babel

34,191
Apache 2.0
Used by 55
61Health
Tool npm

style-loader

A webpack loader that injects bundled CSS into the DOM using style or link tags at runtime.

1,666
MIT
Used by 54
73Health
Tool npm

babel-loader

Babel loader for webpack (and Rspack) that transpiles modern JavaScript with filesystem caching and source map support.

4,835
MIT
Used by 51
82Health
Tool npm

sass-loader

Compiles Sass and SCSS files to CSS inside a webpack build, wiring in Dart Sass or Sass Embedded automatically.

3,891
MIT
Used by 48
90Health
Tool PyPI

Ruff

An extremely fast Python linter and code formatter, written in Rust, built as a drop-in replacement for Flake8, Black, isort, and dozens of plugins.

49,630
MIT
Used by 46
46Health
Tool npm

npm-run-all

A cross-platform CLI that runs multiple npm-scripts in parallel or in sequence, replacing fragile shell operators like && with Windows-safe orchestration.

5,832
MIT
Used by 41
78Health
Tool npm

TypeScript Native Preview

Preview npm build of tsgo, the native Go port of the TypeScript compiler ahead of TypeScript 7.0.

26,194
Apache 2.0
Used by 34
90Health
Tool PyPI

Gunicorn

A fast, lightweight pre-fork WSGI and ASGI HTTP server for running Python web apps in production on UNIX.

10,669
MIT
Used by 33
95Health
Tool npm

mocha

The classic, battle-tested JavaScript test framework for Node.js and the browser, built around flexible async testing and pluggable reporters.

22,896
MIT
Used by 30
84Health
Tool PyPI

mypy

Optional static type checker that catches Python bugs before you run your code

20,640
MIT
Used by 30
89Health
Tool PyPI

Alembic

Database migrations tool for SQLAlchemy with autogenerate and transactional DDL

4,393
MIT
Used by 26

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