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

90Health
Library npm

Tailwind CSS

A utility-first CSS framework for rapidly building custom user interfaces without leaving your markup.

97,558
MIT
Used by 340
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
87Health
Library npm

tailwind-merge

Merge Tailwind CSS classes without style conflicts

5,688
MIT
Used by 218
88Health
Library npm

Autoprefixer

Parses your CSS and automatically adds vendor prefixes using real-world browser usage data from Can I Use.

22,229
MIT
Used by 198
83Health
Library npm

class-variance-authority

A tiny TypeScript utility for building type-safe, variant-driven className APIs on top of clsx.

6,888
Apache 2.0
Used by 190
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
34Health
Library npm

tailwindcss-animate

Tailwind CSS plugin for enter and exit animations using utility classes

3,018
MIT
Used by 100
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
42Health
Library npm

tw-animate-css

A pure-CSS, Tailwind CSS v4 compatible replacement for tailwindcss-animate.

802
MIT
Used by 97
70Health
Library npm

Fontsource Inter

Self-host the Inter typeface with a single npm install and zero third-party font requests.

495
Other
Used by 78
60Health
Library npm

diff

A battle-tested JavaScript library for computing and applying text diffs at the character, word, line, sentence, CSS, or JSON level.

9,207
BSD 3
Used by 70
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
59Health
Library npm

classnames

A tiny utility for conditionally joining CSS class names together.

17,777
MIT
Used by 68
63Health
Library npm

Emotion

Performant, flexible CSS-in-JS styling for React with the css prop, theming, and SSR support

18,016
MIT
Used by 66
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

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