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

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.

28,977
MIT
Used by 277
94Health
Library npm

Marked

A fast, low-level Markdown compiler that parses CommonMark and GFM into HTML in Node.js, browsers, or the CLI.

37,214
MIT
Used by 112
82Health
Library npm

js-yaml

A fast, complete YAML 1.2 and 1.1 parser and serializer for JavaScript.

6,634
MIT
Used by 101
88Health
Library npm

yaml

A definitive TypeScript parser and stringifier for YAML, supporting 1.1 and 1.2 with comment and CST access.

1,692
Other
Used by 99
62Health
Framework npm

Commander.js

The complete, battle-tested framework for building Node.js command-line interfaces.

28,412
MIT
Used by 94
91Health
Framework PyPI

FastAPI

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

102,676
MIT
Used by 78
63Health
Library Cargo

url

A WHATWG-standard-compliant URL parser and manipulation library for Rust.

1,575
Apache 2.0
Used by 62
79Health
Library npm

PapaParse

The fastest in-browser CSV parser for JavaScript, with streaming, Web Workers, and zero dependencies

13,576
MIT
Used by 61
90Health
Library Cargo

Clap

The most widely used command-line argument parser for Rust, with both derive and builder APIs.

16,725
Other
Used by 56
78Health
Library npm

markdown-it

A fast, pluggable CommonMark-compliant Markdown parser and renderer for JavaScript, safe by default.

21,945
MIT
Used by 52
57Health
Library PyPI

rich

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

57,443
MIT
Used by 47
90Health
Library npm

Cheerio

The fast, flexible library for parsing and manipulating HTML and XML with a familiar jQuery-style API.

30,505
MIT
Used by 45
75Health
Framework npm

yargs

The modern, pirate-themed command-line argument parser and command framework for Node.js

11,504
MIT
Used by 42
84Health
Library npm

sanitize-html

Allowlist-based HTML sanitizer that strips XSS vectors from untrusted markup while preserving the tags and attributes you choose to keep.

4,630
MIT
Used by 42
91Health
Library npm

BullMQ

Fast, reliable Redis-based message queue and background job processing for Node.js and TypeScript.

9,442
MIT
Used by 41
82Health
Library npm

body-parser

Node.js body-parsing middleware that turns raw HTTP request bodies into ready-to-use req.body objects.

5,499
MIT
Used by 36
92Health
Framework Composer

PHPUnit

The de facto standard, programmer-oriented unit testing framework for PHP.

20,057
BSD 3
Used by 34
84Health
Library npm

cron-parser

Parse, validate, and iterate cron expressions in Node.js with full timezone and DST support.

1,495
MIT
Used by 34
84Health
Library npm

cRonstrue

Turns cron expressions into human-readable descriptions, in 30+ languages.

1,636
MIT
Used by 33
81Health
Library npm

fast-xml-parser

Pure-JS XML parser, builder, and validator with no C/C++ bindings and no callbacks

3,139
MIT
Used by 32
92Health
Library Composer

Guzzle

An extensible PHP HTTP client for sending requests and integrating with web services

23,452
MIT
Used by 31
38Health
Library npm

gray-matter

Fast, dependable front-matter parser for YAML, JSON, TOML, and CoffeeScript metadata blocks

4,491
MIT
Used by 31
90Health
Library PyPI

websockets

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

5,719
BSD 3
Used by 30
77Health
Library npm

csv-parse

A flexible, dependency-free CSV parser for Node.js and the browser with stream, callback, and sync APIs.

4,287
MIT
Used by 29

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