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
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
Framework Cargo

Tokio

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

33,150
MIT
Used by 95
91Health
Tool PyPI

Uvicorn

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

10,963
BSD 3
Used by 81
51Health
Library npm

cors

Node.js CORS middleware for Express and Connect that sets standards-compliant headers to control cross-origin browser access.

6,194
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
92Health
Library Cargo

futures

The foundational Future, Stream, and Sink traits and combinators for zero-cost async Rust

5,921
Apache 2.0
Used by 65
90Health
Framework npm

Hono

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

32,186
MIT
Used by 60
82Health
Library npm

RxJS

The standard library for composing asynchronous and event-based programs using observable sequences

31,698
Apache 2.0
Used by 53
51Health
Library npm

cookie-parser

Express middleware that parses HTTP Cookie headers into req.cookies, with support for signed and JSON-encoded cookie values.

2,030
MIT
Used by 52
60Health
Library npm

p-limit

A tiny, battle-tested utility for running async functions with a strict concurrency limit.

2,925
MIT
Used by 45
87Health
Library npm

Multer

Streamlined multipart/form-data file upload handling for Express and Node.js APIs.

12,085
MIT
Used by 44
76Health
Library Cargo

async-trait

Type erasure for async fn in Rust traits, enabling async methods behind dyn dispatch.

2,196
Other
Used by 43
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
82Health
Library npm

@hono/node-server

The official Node.js adapter that runs your Hono application on a native Node HTTP server using web-standard APIs.

676
MIT
Used by 37
84Health
Library npm

body-parser

Node.js body-parsing middleware that turns raw HTTP request bodies into ready-to-use req.body objects.

5,499
MIT
Used by 36
90Health
Framework npm

tRPC Server

Build end-to-end typesafe APIs in TypeScript with no schemas, no code generation, and zero runtime bloat.

40,607
MIT
Used by 35
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
89Health
Library npm

@hono/zod-validator

Type-safe request validation middleware for Hono, powered by Zod schemas.

992
MIT
Used by 34
90Health
Tool PyPI

Gunicorn

A fast, lightweight pre-fork WSGI and ASGI HTTP server for running Python web apps in production on UNIX.

10,669
MIT
Used by 33
72Health
Library npm

compression

Node.js middleware that transparently gzip-, deflate-, or Brotli-compresses HTTP responses for Express and raw http servers.

2,806
MIT
Used by 33
90Health
Library PyPI

websockets

Build correct, fast WebSocket servers and clients in Python with asyncio, threading, or Sans-I/O APIs.

5,717
BSD 3
Used by 29
92Health
Framework Cargo

axum

Ergonomic and modular HTTP routing and request-handling framework for Rust, built on Tokio, Hyper, and Tower.

27,128
MIT
Used by 28
93Health
Framework npm

NestJS

A progressive Node.js framework for building efficient, scalable, and maintainable server-side applications in TypeScript.

76,663
MIT
Used by 27

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