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
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
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
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
62Health
Library PyPI

rich

A Python library for rendering rich text, tables, progress bars, and syntax-highlighted code in the terminal.

57,363
MIT
Used by 46
90Health
Tool PyPI

Ruff

An extremely fast Python linter and code formatter, written in Rust, built as a drop-in replacement for Flake8, Black, isort, and dozens of plugins.

49,630
MIT
Used by 46
90Health
Library npm

Prisma Client

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

47,610
Apache 2.0
Used by 46
86Health
Library PyPI

typing_extensions

Backported and experimental type-hint features for Python, usable on older interpreters and ahead of the stdlib.

582
Other
Used by 45
92Health
SDK npm

@clickhouse/client

The official TypeScript client for connecting Node.js applications to ClickHouse over HTTP.

331
Apache 2.0
Used by 38
40Health
Library npm

unist-util-visit

Tiny utility to walk unist syntax trees and run a visitor on matching nodes

357
MIT
Used by 36
83Health
Library npm

type-fest

A collection of essential, ready-made TypeScript utility types beyond the built-in standard library.

17,409
Other
Used by 32
90Health
Library PyPI

websockets

Build correct, fast WebSocket servers and clients in Python with asyncio, threading, or Sans-I/O APIs.

5,717
BSD 3
Used by 29
90Health
Framework PyPI

Typer

Typer is a Python library for building CLI applications, using type hints to generate arguments, options, validation, help text, and shell completion automatically.

19,983
MIT
Used by 26
50Health
Library npm

ms

Tiny millisecond conversion utility for parsing and formatting human-readable time strings

5,548
MIT
Used by 24
63Health
Library npm

async

Higher-order async utility functions for callback, async/await, and promise-based control flow in Node.js and the browser.

28,131
MIT
Used by 23
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
69Health
Library npm

globby

User-friendly glob matching for Node.js, built on fast-glob with negation, directory expansion, and gitignore support.

2,649
MIT
Used by 19
48Health
Library npm

forge

A native, pure-JavaScript implementation of TLS and PKI cryptography for building crypto-based Node.js and browser apps.

5,331
Other
Used by 17
91Health
Library PyPI

Celery

Distributed task queue for running asynchronous jobs, scheduled work, and complex workflows across Python applications at scale.

28,883
BSD 3
Used by 16
84Health
Library npm

got

Human-friendly and powerful HTTP request library for Node.js, with retries, streams, pagination, and RFC 7234 caching built in.

14,940
MIT
Used by 15
45Health
Library npm

mdast-util-from-markdown

Parses markdown into a fully spec-compliant mdast syntax tree using the micromark tokenizer.

290
MIT
Used by 15
91Health
Framework Go

Echo

A minimalist, high-performance Go web framework with a radix-tree router, built-in middleware chain, and first-class HTTP/2 support.

32,705
MIT
Used by 13
42Health
Library npm

GSAP

The industry-standard JavaScript animation library for tweening CSS, SVG, canvas, and UI with rock-solid cross-browser reliability.

28,405
Other
Used by 11

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