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

82Health
Library npm

body-parser

Node.js body-parsing middleware that turns raw HTTP request bodies into ready-to-use req.body objects.

5,499
MIT
Used by 36
92Health
Framework Composer

PHPUnit

The de facto standard, programmer-oriented unit testing framework for PHP.

20,057
BSD 3
Used by 34
84Health
Library npm

cron-parser

Parse, validate, and iterate cron expressions in Node.js with full timezone and DST support.

1,495
MIT
Used by 34
88Health
Tool PyPI

Gunicorn

A fast, lightweight pre-fork WSGI and ASGI HTTP server for running Python web apps in production on UNIX.

10,686
MIT
Used by 33
93Health
Library PyPI

OpenTelemetry Python SDK

The reference implementation of the OpenTelemetry API for Python - traces, metrics, and logs

2,649
Apache 2.0
Used by 33
84Health
Library npm

cRonstrue

Turns cron expressions into human-readable descriptions, in 30+ languages.

1,636
MIT
Used by 33
81Health
Library npm

fast-xml-parser

Pure-JS XML parser, builder, and validator with no C/C++ bindings and no callbacks

3,139
MIT
Used by 32
92Health
Library Composer

Guzzle

An extensible PHP HTTP client for sending requests and integrating with web services

23,452
MIT
Used by 31
38Health
Library npm

gray-matter

Fast, dependable front-matter parser for YAML, JSON, TOML, and CoffeeScript metadata blocks

4,491
MIT
Used by 31
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
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
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
65Health
Library npm

query-string

Parse and stringify URL query strings in JavaScript with flexible array, number, and boolean handling.

6,909
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
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
83Health
Library PyPI

asyncpg

A fast PostgreSQL database client library for Python built directly on asyncio, implementing the PostgreSQL binary wire protocol natively for high-throughput async applications.

8,094
Apache 2.0
Used by 26
96Health
SDK PyPI

sentry-sdk

The official Python SDK for Sentry error tracking, performance monitoring, and tracing.

2,208
MIT
Used by 25
80Health
Library PyPI

idna

Internationalized Domain Names for Python — IDNA 2008 and UTS #46 encoding and decoding

295
BSD 3
Used by 25
87Health
Framework PyPI

Django

The high-level Python web framework that turns database models into secure, working web applications in record time.

91,218
BSD 3
Used by 24
94Health
Library PyPI

pypdf

A pure-Python library for splitting, merging, cropping, transforming, and extracting content from PDF files.

10,232
BSD 3
Used by 24

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