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

75Health
Library npm

qs

A battle-tested querystring parser and serializer for Node.js with nested object support and built-in security limits.

8,940
BSD 3
Used by 49
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
53Health
Library PyPI

python-dateutil

Powerful extensions to Python's datetime module for parsing, deltas, recurrence, and timezones.

2,634
Other
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
53Health
Library PyPI

Jinja

A fast, expressive, and extensible templating engine for Python.

11,776
BSD 3
Used by 45
85Health
Library PyPI

PyJWT

A Python implementation of RFC 7519 for encoding, decoding, and verifying JSON Web Tokens.

5,700
MIT
Used by 44
72Health
Library PyPI

psycopg2

The most popular PostgreSQL database adapter for Python, implementing the full DB API 2.0 specification.

3,654
Other
Used by 42
91Health
Library npm

BullMQ

Fast, reliable Redis-based message queue and background job processing for Node.js and TypeScript.

9,396
MIT
Used by 41
95Health
Framework PyPI

aiohttp

Asynchronous HTTP client and server framework for Python's asyncio, covering both API calls and building web/WebSocket services.

16,548
Apache 2.0
Used by 40
86Health
Library PyPI

psutil

Cross-platform Python library for retrieving process and system utilization data.

11,273
BSD 3
Used by 40
96Health
Library PyPI

PyTorch

A Python-first tensor library with GPU acceleration and a dynamic, define-by-run autograd engine for building and training deep neural networks.

103,008
BSD 3
Used by 39
92Health
Framework npm

Astro

The web framework for building fast, content-driven websites with islands architecture.

62,548
MIT
Used by 39
95Health
SDK PyPI

redis-py

The official Python client for Redis, with sync, asyncio, cluster, and Sentinel support.

13,640
MIT
Used by 39
75Health
Library npm

turndown

Convert HTML into clean, customizable Markdown in Node.js and the browser.

11,438
MIT
Used by 38
80Health
Library npm

@clack/prompts

Opinionated, ready-to-use interactive prompt components for building beautiful command-line apps in Node.js.

8,051
MIT
Used by 38
94Health
Library PyPI

OpenTelemetry Prometheus Exporter

Export OpenTelemetry metrics in Prometheus format so Prometheus can scrape your Python application.

2,631
Apache 2.0
Used by 38
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
95Health
Framework PyPI

Transformers

State-of-the-art pretrained models for text, vision, audio, and multimodal inference and training.

165,971
Apache 2.0
Used by 37
89Health
Library PyPI

tqdm

A fast, extensible progress bar for Python loops and CLI pipelines, with negligible overhead.

31,335
Other
Used by 37
94Health
Library PyPI

SQLAlchemy

The Python SQL toolkit and Object Relational Mapper that gives developers the full power and flexibility of SQL.

12,156
MIT
Used by 37
89Health
SDK PyPI

python-sdk

The official Python SDK for building Model Context Protocol servers and clients that expose tools, resources, and prompts to any LLM host.

24,294
MIT
Used by 36
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

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