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

82Health
Library PyPI

Requests

The elegant, human-friendly HTTP library that made Python's most-used API for talking to the web.

54,300
Apache 2.0
Used by 110
79Health
Tool npm

concurrently

Run multiple terminal commands in parallel, with color-coded output and cross-platform support.

7,848
MIT
Used by 103
93Health
Library PyPI

Pydantic

Data validation and settings management using Python type hints, backed by a Rust core.

28,772
MIT
Used by 102
96Health
Framework PyPI

pytest

The Python testing framework that makes writing small tests easy and scales to complex functional test suites.

14,506
MIT
Used by 100
64Health
Library npm

Chalk

The most popular Node.js library for styling terminal string output with ANSI colors.

23,315
MIT
Used by 98
54Health
Library PyPI

HTTPX

A next-generation HTTP client for Python with sync, async, and HTTP/2 support

15,478
BSD 3
Used by 85
91Health
Tool PyPI

Uvicorn

A lightning-fast ASGI server for Python, built on uvloop and httptools.

10,963
BSD 3
Used by 81
96Health
Library PyPI

NumPy

The fundamental N-dimensional array library powering Python's scientific computing stack.

32,741
BSD 3
Used by 80
55Health
Library PyPI

PyYAML

A full-featured YAML parser and emitter for Python, with C-accelerated bindings

2,942
MIT
Used by 79
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
65Health
Library PyPI

python-dotenv

Load environment variables from a .env file into Python's os.environ, the standard way to keep 12-factor config out of your code

8,876
BSD 3
Used by 72
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
55Health
Framework Go

Cobra

The commander library that powers Kubernetes, Hugo, and GitHub CLI's command-line interfaces.

44,603
Apache 2.0
Used by 62
98Health
Library PyPI

pandas

The Python DataFrame library for fast, flexible, and expressive data analysis and manipulation.

49,732
BSD 3
Used by 61
92Health
Library PyPI

Pillow

The friendly PIL fork that adds image processing capabilities to Python

13,812
Other
Used by 60
91Health
SDK PyPI

boto3

The official AWS SDK for Python — call every Amazon Web Services API from your code.

9,900
Apache 2.0
Used by 59
96Health
SDK PyPI

OpenAI Python SDK

The official Python library for the OpenAI REST API, generated from OpenAI's OpenAPI spec with typed sync and async clients.

31,622
Apache 2.0
Used by 57
90Health
Library npm

xterm.js

A fast, self-contained TypeScript library for embedding fully-featured terminals in the browser.

21,173
MIT
Used by 57
90Health
Library Cargo

Clap

The most widely used command-line argument parser for Rust, with both derive and builder APIs.

16,707
Other
Used by 56
84Health
Library PyPI

cryptography

The standard cryptographic library for Python, pairing safe high-level recipes with low-level primitives backed by Rust and OpenSSL.

7,765
Other
Used by 53
88Health
Library PyPI

Click

A composable Python toolkit for building command line interfaces with minimal boilerplate.

17,664
BSD 3
Used by 50
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

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