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

83Health
Tool PyPI

mypy

Optional static type checker that catches Python bugs before you run your code

20,651
MIT
Used by 30
90Health
Library PyPI

websockets

Build correct, fast WebSocket servers and clients in Python with asyncio, threading, or Sans-I/O APIs.

5,719
BSD 3
Used by 30
81Health
Library npm

express-rate-limit

Basic IP rate-limiting middleware for Express to throttle repeated requests and protect public APIs and sensitive endpoints.

3,305
MIT
Used by 30
98Health
Library npm

three.js

The cross-browser JavaScript 3D library that renders scenes through WebGL and WebGPU behind one unified, node-based shading API.

115,997
MIT
Used by 29
56Health
Library npm

knex

A flexible, portable SQL query builder for Node.js supporting PostgreSQL, MySQL, CockroachDB, SQL Server, SQLite3, and Oracle.

20,347
MIT
Used by 29
77Health
Library npm

csv-parse

A flexible, dependency-free CSV parser for Node.js and the browser with stream, callback, and sync APIs.

4,287
MIT
Used by 29
81Health
Library PyPI

Psycopg

The modern PostgreSQL adapter for Python, with native async and pipeline support

2,504
Other
Used by 29
77Health
Library npm

ignore

A pure JavaScript manager, filter, and parser for .gitignore-style rules, built exactly to the gitignore spec.

502
MIT
Used by 29
81Health
Framework PyPI

Flask

A lightweight WSGI web framework for Python that scales from a single file to complex applications.

74,802
BSD 3
Used by 28
94Health
Library PyPI

scikit-learn

Simple and efficient tools for machine learning and data analysis in Python.

67,403
BSD 3
Used by 28
57Health
Library npm

ts-morph

Navigate and manipulate TypeScript code with a friendlier compiler API wrapper

6,194
MIT
Used by 28
94Health
SDK npm

supabase-js

The official isomorphic JavaScript SDK for Supabase — database, auth, realtime, storage, and edge functions in one client.

4,568
MIT
Used by 28
50Health
Library npm

react-textarea-autosize

A drop-in <textarea> replacement for React that automatically grows and shrinks to fit its content.

2,410
MIT
Used by 28
97Health
SDK npm

@azure/identity

Microsoft Entra ID credential library that authenticates every Azure SDK client, from managed identity in production to CLI and browser login in development.

2,296
MIT
Used by 28
44Health
Library npm

date-fns-tz

IANA time zone support for date-fns, powered by the native Intl API with zero bundled time zone data.

1,180
MIT
Used by 28
92Health
Framework npm

NestJS

A progressive Node.js framework for building efficient, scalable, and maintainable server-side applications in TypeScript.

76,743
MIT
Used by 27
88Health
Framework npm

Expo

Open-source framework for building universal native apps with React that run on Android, iOS, and the web.

52,467
MIT
Used by 27
90Health
Library npm

react-grid-layout

A responsive, draggable, and resizable grid layout system for React with breakpoints and zero jQuery.

22,436
MIT
Used by 27
85Health
Library npm

Chai

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

8,268
MIT
Used by 27
89Health
Tool PyPI

Alembic

Database migrations tool for SQLAlchemy with autogenerate and transactional DDL

4,413
MIT
Used by 27
89Health
Library PyPI

pydantic-settings

Type-safe application settings management for Python, built on Pydantic models.

1,462
MIT
Used by 27
72Health
Library npm

NextAuth.js

Open-source authentication for Next.js with OAuth, OIDC, email, and passkey sign-in.

28,374
Other
Used by 26
75Health
Library npm

validator.js

A dependency-free library of 100+ string validators and sanitizers for Node.js and the browser.

23,736
MIT
Used by 26
89Health
Framework PyPI

Typer

Typer is a Python library for building CLI applications, using type hints to generate arguments, options, validation, help text, and shell completion automatically.

20,033
MIT
Used by 26

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