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

Prisma Client

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

47,610
Apache 2.0
Used by 46
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

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