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

91Health
Tool npm

prettier

An opinionated code formatter that enforces consistent style across every language your project speaks.

52,316
MIT
Used by 310
72Health
Library Cargo

serde_json

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

5,638
Apache 2.0
Used by 113
81Health
Library PyPI

Requests

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

54,353
Apache 2.0
Used by 112
76Health
Library Cargo

serde

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

10,838
Other
Used by 109
92Health
Library npm

AI SDK

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

26,955
Apache 2.0
Used by 105
93Health
Library PyPI

Pydantic

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

28,891
MIT
Used by 104
75Health
Library Go

testify

The essential Go toolkit for assertions, mocks, and structured test suites.

26,217
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.

14,543
MIT
Used by 100
95Health
Framework Cargo

Tokio

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

33,257
MIT
Used by 96
56Health
Library PyPI

HTTPX

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

15,517
BSD 3
Used by 86
64Health
Library npm

fs-extra

Drop-in replacement for Node's fs module adding copy, remove, mkdirs, and JSON helpers with native promise support.

9,590
MIT
Used by 84
91Health
Tool PyPI

Uvicorn

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

10,993
BSD 3
Used by 83
95Health
Library PyPI

NumPy

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

32,864
BSD 3
Used by 82
53Health
Library PyPI

PyYAML

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

2,950
MIT
Used by 80
91Health
Framework PyPI

FastAPI

A modern, high-performance Python web framework for building APIs with automatic validation, serialization, and interactive docs.

102,676
MIT
Used by 78
63Health
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

8,883
BSD 3
Used by 73
82Health
Library Cargo

reqwest

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

11,845
Other
Used by 72
63Health
Library npm

diff

A battle-tested JavaScript library for computing and applying text diffs at the character, word, line, sentence, CSS, or JSON level.

9,210
BSD 3
Used by 70
68Health
Library Cargo

tempfile

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

1,468
Other
Used by 69
85Health
Library npm

Pino

A super fast, low-overhead JSON logger for Node.js applications.

18,227
MIT
Used by 67
66Health
Library Cargo

base64

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

738
Apache 2.0
Used by 66
54Health
Framework Go

Cobra

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

44,650
Apache 2.0
Used by 62
92Health
Library PyPI

Pillow

The friendly PIL fork that adds image processing capabilities to Python

13,856
Other
Used by 62
65Health
Library Go

jwt

A zero-dependency Go implementation of JSON Web Tokens (JWT) with pluggable HMAC, RSA, RSA-PSS, ECDSA, and Ed25519 signing methods.

9,230
MIT
Used by 62

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