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.

52,316
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.

28,977
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.

16,401
MIT
Used by 260
72Health
Library Cargo

serde_json

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

5,638
Apache 2.0
Used by 113
94Health
Library npm

Marked

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

37,214
MIT
Used by 112
76Health
Library Cargo

serde

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

10,838
Other
Used by 109
82Health
Library npm

js-yaml

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

6,634
MIT
Used by 101
88Health
Library npm

yaml

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

1,692
Other
Used by 99
95Health
Framework Cargo

Tokio

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

33,257
MIT
Used by 96
62Health
Framework npm

Commander.js

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

28,412
MIT
Used by 94
64Health
Library npm

fs-extra

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

9,590
MIT
Used by 84
91Health
Framework PyPI

FastAPI

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

102,676
MIT
Used by 78
82Health
Library Cargo

reqwest

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

11,845
Other
Used by 72
90Health
Tool npm

Oxlint

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

22,902
MIT
Used by 70
63Health
Library npm

diff

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

9,210
BSD 3
Used by 70
68Health
Library Cargo

tempfile

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

1,468
Other
Used by 69
85Health
Library npm

Pino

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

18,227
MIT
Used by 67
66Health
Library Cargo

base64

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

738
Apache 2.0
Used by 66
63Health
Library Cargo

url

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

1,575
Apache 2.0
Used by 62
79Health
Library npm

PapaParse

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

13,576
MIT
Used by 61
67Health
Library Cargo

sha2

Pure Rust implementation of the SHA-2 hash function family (SHA-224/256/384/512) with hardware-accelerated backends.

2,267
Other
Used by 61
77Health
Library Cargo

regex

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

4,038
Apache 2.0
Used by 59
73Health
Library Cargo

Chrono

Timezone-aware date and time handling for Rust, with correct calendar operations and flexible strftime-style formatting.

3,913
Other
Used by 59
90Health
Tool npm

SWC

Rust-based JavaScript/TypeScript compiler, a drop-in super-fast alternative to Babel

34,208
Apache 2.0
Used by 56

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