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.

28,972
MIT
Used by 277
95Health
Library npm

Marked

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

37,141
MIT
Used by 112
82Health
Library npm

js-yaml

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

6,630
MIT
Used by 101
90Health
Library npm

yaml

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

1,691
Other
Used by 98
92Health
Library npm

undici

A fast, spec-compliant HTTP/1.1 client for Node.js, built from scratch with zero runtime dependencies

7,695
MIT
Used by 70
66Health
Library Cargo

url

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

1,576
Apache 2.0
Used by 62
81Health
Library npm

PapaParse

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

13,568
MIT
Used by 61
90Health
Library Cargo

Clap

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

16,707
Other
Used by 56
79Health
Library npm

markdown-it

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

21,901
MIT
Used by 52
93Health
Library PyPI

urllib3

A powerful, user-friendly HTTP client for Python with thread-safe connection pooling, TLS verification, and retry handling.

4,058
MIT
Used by 48
68Health
Library npm

proxy-agent

Maps HTTP, HTTPS, SOCKS, and PAC proxy protocols to the correct Node.js http.Agent implementation automatically.

1,161
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.

30,483
MIT
Used by 45
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.

4,619
MIT
Used by 42
84Health
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
86Health
Library npm

cron-parser

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

1,490
MIT
Used by 34
89Health
Library npm

cRonstrue

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

1,632
MIT
Used by 33
87Health
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
38Health
Library npm

gray-matter

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

4,490
MIT
Used by 31
70Health
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
84Health
Library npm

http-proxy-middleware

The one-liner Node.js proxy middleware for connect, express, next.js, hono, and more.

11,126
MIT
Used by 20
37Health
Library npm

minimist

A lightweight, dependency-free argument parser that turns process.argv into a clean options object.

661
MIT
Used by 20
47Health
Library npm

tinycolor2

Fast, dependency-free color parsing, conversion, and manipulation for JavaScript

5,250
MIT
Used by 19
59Health
Library npm

Croner

A zero-dependency cron job scheduler and cron-expression evaluator for JavaScript and TypeScript

2,591
MIT
Used by 19
53Health
Library Cargo

csv

Fast, flexible CSV reading and writing for Rust, with Serde support

1,959
Other
Used by 19

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