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

91Health
Tool npm

prettier

An opinionated code formatter that enforces consistent style across every language your project speaks.

52,263
MIT
Used by 310
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
94Health
Tool npm

typescript-eslint

The official meta-package bundling the TypeScript ESLint parser, plugin, and rule presets behind a single typed config() helper.

16,391
MIT
Used by 260
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
75Health
Library Cargo

serde_json

The de facto standard JSON library for Rust, built on the Serde serialization framework

5,636
Apache 2.0
Used by 111
95Health
SDK npm

Sentry JavaScript (@sentry/browser)

The official Sentry SDK for capturing errors, performance traces, and session replays in browser JavaScript apps.

8,742
MIT
Used by 110
76Health
Library Cargo

serde

A generic framework for serializing and deserializing Rust data structures efficiently and safely.

10,825
Other
Used by 108
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
93Health
Framework Cargo

Tokio

The async runtime powering most of Rust's networked, concurrent, and I/O-bound applications.

33,150
MIT
Used by 95
63Health
Framework npm

Commander.js

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

28,391
MIT
Used by 94
56Health
Library npm

fs-extra

Drop-in replacement for Node's fs module adding copy, remove, mkdirs, and JSON helpers with native promise support.

9,589
MIT
Used by 84
95Health
Tool npm

Storybook

The industry-standard workshop for building, documenting, and testing UI components in isolation, across every major frontend framework.

91,053
MIT
Used by 83
90Health
Framework PyPI

FastAPI

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

102,333
MIT
Used by 76
90Health
Tool npm

Oxlint

Rust-based JavaScript/TypeScript linter that runs 50-100x faster than ESLint, with zero configuration required.

22,741
MIT
Used by 70
84Health
Library Cargo

reqwest

An ergonomic, batteries-included HTTP client for Rust, with async and blocking APIs.

11,821
Other
Used by 70
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
73Health
Library Cargo

tempfile

A secure, cross-platform Rust library for temporary files and directories that clean up automatically on drop.

1,463
Other
Used by 68
83Health
Library npm

Pino

A super fast, low-overhead JSON logger for Node.js applications.

18,194
MIT
Used by 67
67Health
Library Cargo

base64

Correct, fast, and configurable base64 encoding and decoding for Rust, with pluggable alphabets and padding.

736
Apache 2.0
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
79Health
Library Cargo

regex

Rust's finite-automata regex engine with guaranteed linear-time matching and no catastrophic backtracking.

4,024
Apache 2.0
Used by 58

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