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
94Health
Tool npm

typescript-eslint

The official meta-package bundling the TypeScript ESLint parser, plugin, and rule presets behind a single typed config() helper.

16,401
MIT
Used by 260
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
85Health
Framework npm

Express

The fast, unopinionated, minimalist web framework for Node.js

69,493
MIT
Used by 158
94Health
SDK npm

AWS SDK for JavaScript (S3 Client)

The official modular AWS SDK v3 client for Amazon S3, with TypeScript-first APIs and streaming support.

3,668
Apache 2.0
Used by 129
84Health
Library npm

ws

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

22,807
MIT
Used by 116
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
75Health
Library Go

testify

The essential Go toolkit for assertions, mocks, and structured test suites.

26,217
MIT
Used by 102
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
62Health
Framework npm

Commander.js

The complete, battle-tested framework for building Node.js command-line interfaces.

28,412
MIT
Used by 94
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
95Health
SDK npm

OpenAI

The official Node.js/TypeScript client for the OpenAI API, auto-generated from OpenAI's own OpenAPI spec.

11,192
Apache 2.0
Used by 86
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
90Health
Tool npm

Oxlint

Rust-based JavaScript/TypeScript linter that runs 50-100x faster than ESLint, with zero configuration required.

22,902
MIT
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
97Health
Framework npm

Electron

Build cross-platform desktop apps with JavaScript, HTML, and CSS on Chromium and Node.js

123,289
MIT
Used by 69

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