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
34Health
Library npm

tailwindcss-animate

Tailwind CSS plugin for enter and exit animations using utility classes

3,018
MIT
Used by 100
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
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
60Health
Library npm

Font Awesome Free

The internet's icon toolkit — thousands of SVG, web font, and CSS icons for the web

76,922
Other
Used by 41
65Health
Library npm

postcss-import

A PostCSS plugin that inlines @import rules, merging split CSS files into one stylesheet before other plugins run.

1,410
MIT
Used by 33
89Health
Library npm

styled-components

Write actual CSS in your React components and let styled-components scope, inject, and dedupe it at runtime.

41,104
MIT
Used by 30
45Health
Library npm

color

Immutable JavaScript color conversion and manipulation with CSS string support

4,934
MIT
Used by 26
90Health
Library npm

cssnano

A modular CSS minifier built on the PostCSS ecosystem, composing dozens of swappable optimization plugins into safe, lite, and advanced presets.

4,976
MIT
Used by 25
78Health
Library npm

postcss-preset-env

Converts tomorrow's CSS syntax into code today's browsers understand by auto-selecting PostCSS polyfill plugins from your browserslist targets.

1,052
Other
Used by 25
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
48Health
Library npm

react-transition-group

react-transition-group: React Component Animation Toolkit

10,220
BSD 3
Used by 20
67Health
Library npm

tailwind-variants

Typed Tailwind CSS variant API with slots, compound variants, and built-in class-conflict resolution

3,297
MIT
Used by 18

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