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

86Health
Framework npm

Express

The fast, unopinionated, minimalist web framework for Node.js

69,454
MIT
Used by 158
96Health
Framework npm

Next.js

The React framework for production: file-based routing, server rendering, and Rust-powered builds.

142,310
MIT
Used by 154
89Health
Tool npm

lint-staged

Run linters and formatters only against the files staged in git, so a slow full-project lint never blocks a commit.

14,731
MIT
Used by 120
75Health
Library Cargo

serde_json

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

5,636
Apache 2.0
Used by 111
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
76Health
Library Cargo

serde

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

10,825
Other
Used by 108
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
93Health
Framework Cargo

Tokio

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

33,150
MIT
Used by 95
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
41Health
Library npm

@codemirror/view

The DOM view layer for the CodeMirror 6 code editor, handling rendering, input, and editor chrome.

178
MIT
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
32Health
Library npm

CodeMirror State

Immutable document, selection, and transaction data structures for the CodeMirror code editor

83
MIT
Used by 73
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
53Health
Library npm

@monaco-editor/react

Drop the Monaco code editor into any React app without touching webpack, rollup, or bundler config files.

4,741
MIT
Used by 72
84Health
Library Cargo

reqwest

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

11,821
Other
Used by 70
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
73Health
Library Cargo

tempfile

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

1,463
Other
Used by 68
26Health
Library npm

@codemirror/language

Language support infrastructure for the CodeMirror 6 editor: parsing, indentation, code folding, bracket matching, and syntax highlighting.

32
MIT
Used by 67
67Health
Library Cargo

base64

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

736
Apache 2.0
Used by 66
98Health
Library PyPI

pandas

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

49,732
BSD 3
Used by 61

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