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

92Health
Library npm

postcss

A CSS transformation engine that parses styles into an AST, letting JS plugins lint, prefix, and rewrite CSS — the foundation beneath Autoprefixer, Tailwind, and 200+ other tools.

28,977
MIT
Used by 277
78Health
Library npm

dotenv

Loads environment variables from a .env file into process.env for Node.js apps.

20,543
Other
Used by 227
78Health
Library npm

date-fns

Modern JavaScript date utility library with 200+ pure, immutable functions

36,647
MIT
Used by 202
89Health
Library npm

jsdom

A pure-JavaScript implementation of the WHATWG DOM and HTML standards for Node.js.

21,692
MIT
Used by 200
94Health
Library npm

Axios

Promise-based HTTP client for the browser and Node.js with interceptors, automatic transforms, and cancellation

109,216
MIT
Used by 190
84Health
Library npm

ws

A simple, blazing-fast, thoroughly tested WebSocket client and server library for Node.js.

22,807
MIT
Used by 116
72Health
Library Cargo

serde_json

The de facto standard JSON library for Rust, built on the Serde serialization framework

5,638
Apache 2.0
Used by 113
94Health
Library npm

Marked

A fast, low-level Markdown compiler that parses CommonMark and GFM into HTML in Node.js, browsers, or the CLI.

37,214
MIT
Used by 112
82Health
Library npm

i18next

The internationalization framework for JavaScript, with zero runtime dependencies and a pluggable ecosystem for every environment.

8,637
MIT
Used by 110
90Health
Library npm

sharp

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

32,726
Apache 2.0
Used by 109
82Health
Library npm

js-yaml

A fast, complete YAML 1.2 and 1.1 parser and serializer for JavaScript.

6,634
MIT
Used by 101
88Health
Library npm

yaml

A definitive TypeScript parser and stringifier for YAML, supporting 1.1 and 1.2 with comment and CST access.

1,692
Other
Used by 99
96Health
Library npm

OpenTelemetry JavaScript (@opentelemetry/api)

Vendor-neutral tracing, metrics, and context API that libraries and apps instrument once, so any OpenTelemetry-compatible backend can consume it.

3,479
Apache 2.0
Used by 91
64Health
Library npm

fs-extra

Drop-in replacement for Node's fs module adding copy, remove, mkdirs, and JSON helpers with native promise support.

9,590
MIT
Used by 84
92Health
Library npm

ioredis

A robust, full-featured Redis client for Node.js with built-in Cluster, Sentinel, and TypeScript support.

15,343
MIT
Used by 81
50Health
Library npm

cors

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

6,195
MIT
Used by 79
63Health
Library npm

diff

A battle-tested JavaScript library for computing and applying text diffs at the character, word, line, sentence, CSS, or JSON level.

9,210
BSD 3
Used by 70
92Health
Library npm

undici

A fast, spec-compliant HTTP/1.1 client for Node.js, built from scratch with zero runtime dependencies

7,705
MIT
Used by 70
85Health
Library npm

Pino

A super fast, low-overhead JSON logger for Node.js applications.

18,227
MIT
Used by 67
63Health
Library Cargo

url

A WHATWG-standard-compliant URL parser and manipulation library for Rust.

1,575
Apache 2.0
Used by 62
79Health
Library npm

PapaParse

The fastest in-browser CSV parser for JavaScript, with streaming, Web Workers, and zero dependencies

13,576
MIT
Used by 61
59Health
Library npm

chokidar

Minimal and efficient cross-platform file watching for Node.js.

12,244
MIT
Used by 61
91Health
Library npm

Faker

Generate massive amounts of realistic fake data for testing, seeding, and mocking in JavaScript and TypeScript.

15,502
MIT
Used by 60
79Health
Library npm

Drizzle ORM

A lightweight, zero-dependency TypeScript ORM with full SQL-like query flexibility

35,907
Apache 2.0
Used by 57

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