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

92Health
Library npm

AI SDK

Provider-agnostic TypeScript toolkit for building AI apps and agents with any LLM.

26,733
Apache 2.0
Used by 105
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
85Health
Library npm

Streamdown

A drop-in react-markdown replacement built for AI-powered streaming interfaces.

5,616
Apache 2.0
Used by 51
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
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
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
70Health
Library npm

csv-parse

A flexible, dependency-free CSV parser for Node.js and the browser with stream, callback, and sync APIs.

4,287
MIT
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
53Health
Library npm

jsonrepair

Repair invalid or broken JSON documents — missing quotes, trailing commas, truncation, and more

2,404
Other
Used by 21
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
55Health
Library Composer

Collision

Beautiful command-line error reporting for PHP apps and test suites

4,658
MIT
Used by 18
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
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
78Health
Library npm

Orama

A dependency-free full-text, vector, and hybrid search engine that runs entirely in JavaScript.

10,550
Apache 2.0
Used by 9
37Health
Library npm

fastest-levenshtein

The fastest JavaScript/TypeScript implementation of Levenshtein edit distance

774
MIT
Used by 9
31Health
Library npm

Partial JSON

Parses incomplete JSON strings streamed token-by-token from an LLM into usable JavaScript values as they arrive.

244
MIT
Used by 9
95Health
Library npm

hls.js

JavaScript HLS client that plays HTTP Live Streaming video in the browser via MSE

16,940
Apache 2.0
Used by 8
87Health
Tool PyPI

isort

Automatically sorts and organizes Python import statements

6,951
MIT
Used by 8

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