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

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
48Health
Library npm

bcrypt

Battle-tested password hashing for Node.js using the adaptive bcrypt algorithm.

7,803
MIT
Used by 34
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
65Health
Library PyPI

Certifi

Mozilla's curated root CA bundle for verifying SSL/TLS certificates in Python.

997
MPL-2.0
Used by 32
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
37Health
Library npm

async-mutex

Mutex and semaphore primitives for synchronizing async workflows in JavaScript and TypeScript.

1,434
MIT
Used by 27
40Health
Library Cargo

once_cell

Single-assignment cells and lazy statics for Rust, without macros or unsafe code

2,091
Apache 2.0
Used by 26
91Health
Framework npm

Fastify

A fast and low-overhead web framework for Node.js, built around schema-based validation and a plugin architecture

37,137
MIT
Used by 25
56Health
Library Cargo

tokio-tungstenite

Asynchronous, Tokio-native WebSocket streams built on tungstenite

2,507
MIT
Used by 25
63Health
Library npm

async

Higher-order async utility functions for callback, async/await, and promise-based control flow in Node.js and the browser.

28,131
MIT
Used by 23
94Health
Library Cargo

rustls

A modern, memory-safe TLS library for Rust with no unsafe code and no legacy crypto by default.

7,619
Other
Used by 23
55Health
Library Cargo

Tower

Modular, reusable Rust components for building async network clients and servers

4,294
MIT
Used by 23
71Health
Framework Go

Gin

A high-performance HTTP web framework for Go, built on a zero-allocation radix-tree router with an Express.js-style API.

89,216
MIT
Used by 22
81Health
Library Go

chi

A lightweight, idiomatic Go HTTP router built entirely on net/http, for composing middleware and mounting REST APIs without a framework.

22,827
MIT
Used by 22
64Health
Library Cargo

rayon

Simple, guaranteed data-race-free work-stealing parallelism for Rust — turn sequential iterators parallel by changing one call.

13,313
Apache 2.0
Used by 22
66Health
Library npm

p-queue

Promise queue with concurrency control, interval-based rate limiting, and priority scheduling for async tasks.

4,272
MIT
Used by 22
87Health
Library PyPI

AnyIO

High-level async concurrency and networking API that runs on both asyncio and Trio

2,542
MIT
Used by 22
78Health
Library npm

otplib

TypeScript-first TOTP and HOTP library with a pluggable crypto/base32 architecture for Node, Bun, Deno, and browsers.

2,290
MIT
Used by 22
98Health
Framework Composer

Laravel

The expressive, elegant PHP framework for building modern web applications

34,910
MIT
Used by 21
93Health
Library Cargo

hyper

A fast, low-level HTTP client and server library for Rust supporting HTTP/1 and HTTP/2

16,316
MIT
Used by 21

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