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

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
92Health
Library npm

postcss

A CSS transformation engine that parses styles into an AST, letting JS plugins lint, prefix, and rewrite CSS — the foundation beneath Autoprefixer, Tailwind, and 200+ other tools.

28,972
MIT
Used by 277
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
64Health
Library npm

react-markdown

Safely render Markdown as React elements, no dangerouslySetInnerHTML required

15,878
MIT
Used by 164
95Health
Library npm

@babel/core

The core JavaScript compiler that transforms next-generation syntax into code every browser and runtime can understand.

43,996
MIT
Used by 163
90Health
Framework PyPI

FastAPI

A modern, high-performance Python web framework for building APIs with automatic validation, serialization, and interactive docs.

102,333
MIT
Used by 76
50Health
Library npm

React Syntax Highlighter

A React component for syntax-highlighting code blocks using highlight.js or Prism ASTs, with JavaScript-based styles and no external stylesheet required.

4,674
MIT
Used by 59
66Health
Library npm

remark

A plugin-powered markdown processor that parses, transforms, and serializes markdown on top of unified.

8,995
MIT
Used by 48
62Health
Library PyPI

rich

A Python library for rendering rich text, tables, progress bars, and syntax-highlighted code in the terminal.

57,363
MIT
Used by 46
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
90Health
Library npm

Prisma Client

Auto-generated, type-safe database client for Node.js and TypeScript.

47,610
Apache 2.0
Used by 46
48Health
Library npm

unified

Parse, inspect, transform, and serialize content through syntax-tree plugins.

5,030
MIT
Used by 44
40Health
Library npm

lowlight

Virtual syntax highlighting for virtual DOMs and non-HTML things, powered by highlight.js

923
MIT
Used by 37
40Health
Library npm

unist-util-visit

Tiny utility to walk unist syntax trees and run a visitor on matching nodes

357
MIT
Used by 36
90Health
Library PyPI

websockets

Build correct, fast WebSocket servers and clients in Python with asyncio, threading, or Sans-I/O APIs.

5,717
BSD 3
Used by 29
59Health
Library npm

ts-morph

Navigate and manipulate TypeScript code with a friendlier compiler API wrapper

6,179
MIT
Used by 28
90Health
Framework PyPI

Typer

Typer is a Python library for building CLI applications, using type hints to generate arguments, options, validation, help text, and shell completion automatically.

19,983
MIT
Used by 26
91Health
Library PyPI

Celery

Distributed task queue for running asynchronous jobs, scheduled work, and complex workflows across Python applications at scale.

28,883
BSD 3
Used by 16
50Health
Library npm

rehype

A unified-based HTML processor with a large plugin ecosystem

2,255
MIT
Used by 15
45Health
Library npm

mdast-util-from-markdown

Parses markdown into a fully spec-compliant mdast syntax tree using the micromark tokenizer.

290
MIT
Used by 15
65Health
Library npm

node-sql-parser

Parses SQL statements into an AST and converts them back to SQL across a dozen database dialects.

1,041
Apache 2.0
Used by 13
42Health
Library npm

GSAP

The industry-standard JavaScript animation library for tweening CSS, SVG, canvas, and UI with rock-solid cross-browser reliability.

28,405
Other
Used by 11
74Health
Library npm

micromark

The smallest 100% CommonMark-compliant markdown parser, with GFM and MDX support

2,221
MIT
Used by 11

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