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
51Health
Library npm

jsonwebtoken

The de facto Node.js library for signing, verifying, and decoding JSON Web Tokens.

18,196
MIT
Used by 93
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
89Health
Library npm

jose

Zero-dependency JWT, JWS, JWE, and JWK toolkit for Node.js, browsers, and edge runtimes.

7,792
MIT
Used by 66
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
70Health
Library Cargo

sha2

Pure Rust implementation of the SHA-2 hash function family (SHA-224/256/384/512) with hardware-accelerated backends.

2,265
Other
Used by 55
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
84Health
Library PyPI

cryptography

The standard cryptographic library for Python, pairing safe high-level recipes with low-level primitives backed by Rust and OpenSSL.

7,765
Other
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
56Health
Library npm

bcrypt.js

A zero-dependency, pure JavaScript implementation of bcrypt for hashing and verifying passwords in Node.js and the browser.

3,797
BSD 3
Used by 51
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
85Health
Library PyPI

PyJWT

A Python implementation of RFC 7519 for encoding, decoding, and verifying JSON Web Tokens.

5,700
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
44Health
Library npm

crypto-js

A JavaScript library of crypto standards - hashing, HMAC, PBKDF2, and symmetric ciphers for Node.js and the browser.

16,409
MIT
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

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