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

93Health
Tool npm

Vitest

A blazing-fast unit testing framework powered by Vite, with Jest-compatible APIs out of the box.

17,098
MIT
Used by 294
92Health
Framework npm

Playwright

Cross-browser end-to-end web testing and browser automation with a single API for Chromium, Firefox, and WebKit.

96,127
Apache 2.0
Used by 228
94Health
Tool npm

jest

Delightful JavaScript testing with zero-config setup, snapshots, mocking, and coverage

45,457
MIT
Used by 149
96Health
Framework PyPI

pytest

The Python testing framework that makes writing small tests easy and scales to complex functional test suites.

14,506
MIT
Used by 100
92Health
Library npm

undici

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

7,695
MIT
Used by 70
93Health
Library PyPI

urllib3

A powerful, user-friendly HTTP client for Python with thread-safe connection pooling, TLS verification, and retry handling.

4,058
MIT
Used by 48
68Health
Library npm

proxy-agent

Maps HTTP, HTTPS, SOCKS, and PAC proxy protocols to the correct Node.js http.Agent implementation automatically.

1,161
MIT
Used by 47
90Health
Library npm

Prisma Client

Auto-generated, type-safe database client for Node.js and TypeScript.

47,610
Apache 2.0
Used by 46
93Health
Tool npm

Cypress

Fast, easy, and reliable end-to-end and component testing for anything that runs in a browser.

51,007
MIT
Used by 38
92Health
SDK npm

@clickhouse/client

The official TypeScript client for connecting Node.js applications to ClickHouse over HTTP.

331
Apache 2.0
Used by 38
95Health
Tool npm

mocha

The classic, battle-tested JavaScript test framework for Node.js and the browser, built around flexible async testing and pluggable reporters.

22,896
MIT
Used by 30
86Health
Library npm

Chai

BDD/TDD assertion library for Node.js and the browser, framework-agnostic

8,267
MIT
Used by 27
84Health
Library npm

http-proxy-middleware

The one-liner Node.js proxy middleware for connect, express, next.js, hono, and more.

11,126
MIT
Used by 20
48Health
Library npm

forge

A native, pure-JavaScript implementation of TLS and PKI cryptography for building crypto-based Node.js and browser apps.

5,331
Other
Used by 17
84Health
Library npm

got

Human-friendly and powerful HTTP request library for Node.js, with retries, streams, pagination, and RFC 7234 caching built in.

14,940
MIT
Used by 15
91Health
Framework Go

Echo

A minimalist, high-performance Go web framework with a radix-tree router, built-in middleware chain, and first-class HTTP/2 support.

32,705
MIT
Used by 13
62Health
Tool npm

c8

Native V8 code coverage for Node.js, with Istanbul-compatible reports and zero build-step setup.

2,121
Other
Used by 12
42Health
Library npm

GSAP

The industry-standard JavaScript animation library for tweening CSS, SVG, canvas, and UI with rock-solid cross-browser reliability.

28,405
Other
Used by 11
84Health
Framework Go

Ginkgo

A mature, BDD-style testing framework for Go that pairs with Gomega to write expressive, parallelizable specs.

9,052
MIT
Used by 10
86Health
Tool npm

start-server-and-test

Starts your dev server, waits for it to respond, runs your test command, then shuts the server down automatically.

1,581
MIT
Used by 9
97Health
SDK npm

@azure/msal-browser

Client-side authentication library for browser SPAs, implementing OAuth 2.0 Authorization Code Flow with PKCE against Microsoft Entra ID.

4,119
MIT
Used by 8
83Health
Library npm

jest-extended

Additional custom matchers for Jest to extend and simplify your test assertions.

2,350
MIT
Used by 8
55Health
SDK npm

msgraph-sdk-javascript

Official Microsoft Graph JavaScript SDK for calling the Graph API from Node.js and the browser.

833
MIT
Used by 8
69Health
Tool npm

@vitejs/plugin-basic-ssl

A Vite plugin that generates a self-signed certificate so your dev and preview servers can run over HTTPS with zero setup.

516
MIT
Used by 8

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