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

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
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
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
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
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
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
48Health
Library npm

bcrypt

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

7,803
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
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
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
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
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

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