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

95Health
Library npm

Axios

Promise-based HTTP client for the browser and Node.js with interceptors, automatic transforms, and cancellation

109,212
MIT
Used by 190
86Health
Framework npm

Express

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

69,454
MIT
Used by 158
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
93Health
Library PyPI

Pydantic

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

28,772
MIT
Used by 102
73Health
Library Go

testify

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

26,203
MIT
Used by 102
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
59Health
Library npm

node-fetch

A lightweight, spec-compliant implementation of the browser Fetch API for Node.js

8,855
MIT
Used by 74
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
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
67Health
Library Go

jwt

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

9,225
MIT
Used by 62
90Health
Framework npm

Hono

A small, ultrafast web framework built on Web Standards that runs identically everywhere.

32,186
MIT
Used by 60
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
95Health
SDK Go

AWS SDK for Go v2

The official AWS SDK for Go — type-safe, modular clients for every AWS service.

3,649
Apache 2.0
Used by 44
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
51Health
Library Go

websocket

A fast, RFC 6455-compliant WebSocket implementation for Go with full control over framing, compression, and concurrency.

24,870
Other
Used by 39
96Health
SDK npm

@slack/web-api

Slack's official Node.js HTTP client for calling any of the 270+ Web API methods, with built-in queuing, retries, pagination, and rate-limit handling.

3,378
MIT
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
84Health
Library Go

Logrus

Structured, pluggable logging for Go with a stdlib-compatible API and level-based hooks.

25,746
MIT
Used by 36
49Health
Library Go

mux

A lightweight, http.Handler-compatible Go router that matches requests by path, host, method, headers, and query, and can reverse them back into URLs.

21,836
BSD 3
Used by 35
92Health
Library Go

go-redis

The official, idiomatic Go client for Redis — connection pooling, Cluster, Sentinel, pipelines, and client-side caching built in.

22,234
Other
Used by 34

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