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

89Health
Library npm

sharp

High-performance Node.js image processing powered by libvips, built for fast resizing and format conversion.

32,677
Apache 2.0
Used by 109
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
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
92Health
Library PyPI

Pillow

The friendly PIL fork that adds image processing capabilities to Python

13,812
Other
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
42Health
Library npm

qrcode

A zero-dependency-on-canvas QR code and 2D barcode generator for Node.js and the browser.

8,174
MIT
Used by 53
94Health
Library npm

PDF.js

Mozilla's HTML5-based library for parsing and rendering PDF documents in the browser and Node.js.

53,868
Apache 2.0
Used by 46
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
75Health
Library npm

file-type

Detect the file type of a buffer, stream, or file by reading its magic number.

4,326
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
54Health
Library npm

html-to-image

Turns any DOM node into a PNG, JPEG, SVG, or canvas image entirely client-side, with no server or screenshot service required.

7,235
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
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
74Health
Library npm

qrcode.react

A React component for generating QR codes as SVG or Canvas, with logo embedding and full styling control.

4,284
Other
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
56Health
Library Cargo

tokio-tungstenite

Asynchronous, Tokio-native WebSocket streams built on tungstenite

2,507
MIT
Used by 25
50Health
Library npm

html2canvas

Render live DOM into canvas screenshots entirely in the browser, no server required

31,921
MIT
Used by 23
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
84Health
Tool npm

svgo

A Node.js library and command-line tool that optimizes SVG files by removing redundant markup through a configurable plugin pipeline.

22,669
MIT
Used by 23
55Health
Library Cargo

Tower

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

4,294
MIT
Used by 23
37Health
Library npm

pdf-parse

Pure TypeScript PDF parser for extracting text, images, tables, and metadata in Node.js and browsers.

221
Apache 2.0
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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