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
73Health
Library Go

testify

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

26,203
MIT
Used by 102
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
55Health
Framework Go

Cobra

The commander library that powers Kubernetes, Hugo, and GitHub CLI's command-line interfaces.

44,603
Apache 2.0
Used by 62
67Health
Library Go

jwt

A zero-dependency Go implementation of JSON Web Tokens (JWT) with pluggable HMAC, RSA, RSA-PSS, ECDSA, and Ed25519 signing methods.

9,225
MIT
Used by 62
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
95Health
SDK Go

AWS SDK for Go v2

The official AWS SDK for Go — type-safe, modular clients for every AWS service.

3,649
Apache 2.0
Used by 44
51Health
Library Go

websocket

A fast, RFC 6455-compliant WebSocket implementation for Go with full control over framing, compression, and concurrency.

24,870
Other
Used by 39
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
84Health
Library Go

Logrus

Structured, pluggable logging for Go with a stdlib-compatible API and level-based hooks.

25,746
MIT
Used by 36
49Health
Library Go

mux

A lightweight, http.Handler-compatible Go router that matches requests by path, host, method, headers, and query, and can reverse them back into URLs.

21,836
BSD 3
Used by 35
92Health
Library Go

go-redis

The official, idiomatic Go client for Redis — connection pooling, Cluster, Sentinel, pipelines, and client-side caching built in.

22,234
Other
Used by 34
82Health
Library Go

Go-MySQL-Driver

A pure Go implementation of the MySQL wire protocol, used as the database/sql driver for MySQL, MariaDB, and TiDB.

15,282
MPL-2.0
Used by 33
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
72Health
Library Go

color

Colorized terminal output for Go with ANSI escape codes, 24-bit RGB, and built-in Windows support.

7,999
MIT
Used by 29
50Health
Library Go

go-cmp

A safer, more powerful alternative to reflect.DeepEqual for comparing Go values in tests.

4,676
BSD 3
Used by 29
53Health
Library Go

godotenv

A Go port of Ruby's dotenv that loads environment variables from .env files into your process, with zero third-party dependencies.

10,625
MIT
Used by 27
86Health
Library npm

Chai

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

8,267
MIT
Used by 27

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