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

90Health
Library PyPI

websockets

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

5,717
BSD 3
Used by 29
82Health
Library PyPI

Psycopg

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

2,493
Other
Used by 29
95Health
Library PyPI

scikit-learn

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

67,254
BSD 3
Used by 28
90Health
Library PyPI

pydantic-settings

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

1,456
MIT
Used by 27
52Health
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.

8,088
Apache 2.0
Used by 26
81Health
Library PyPI

idna

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

294
BSD 3
Used by 25
95Health
Library PyPI

pypdf

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

10,202
BSD 3
Used by 23
77Health
Library PyPI

tenacity

A general-purpose Python retrying library that adds configurable retry behavior to almost anything

8,787
Apache 2.0
Used by 23
83Health
Library PyPI

Charset Normalizer

A pure-Python universal charset detector that turns text of unknown encoding into clean Unicode.

794
MIT
Used by 23
98Health
Library PyPI

SciPy

Fundamental algorithms for scientific computing, optimization, and statistics in Python.

15,014
BSD 3
Used by 22
82Health
Library PyPI

attrs

Python classes without boilerplate — generate init, repr, equality, and more from declarative field definitions.

5,839
MIT
Used by 22
73Health
Library PyPI

loguru

A drop-in replacement for Python's standard logging module that makes logging enjoyable, with almost no setup required.

24,105
MIT
Used by 21
97Health
Library PyPI

Matplotlib

Python's foundational plotting library for static, animated, and interactive charts

23,216
Other
Used by 21
89Health
Library PyPI

filelock

A platform-independent file lock for Python that supports the with-statement.

972
MIT
Used by 21
45Health
Library PyPI

markupsafe

Escapes untrusted strings for safe use in HTML and XML markup, preventing injection attacks in templated output.

697
BSD 3
Used by 20
70Health
Library PyPI

orjson

A fast, correct, Rust-backed JSON library for Python with native dataclass, datetime, and numpy support

8,228
Apache 2.0
Used by 19
49Health
Library PyPI

tomli

A lil' TOML parser for Python — fast, spec-compliant, and dependency-free.

570
MIT
Used by 19
91Health
Library PyPI

Celery

Distributed task queue for running asynchronous jobs, scheduled work, and complex workflows across Python applications at scale.

28,883
BSD 3
Used by 16
75Health
Library PyPI

bcrypt (Python)

A Python library for secure password hashing using the bcrypt algorithm with an adjustable work factor

1,503
Apache 2.0
Used by 16
46Health
Library PyPI

itsdangerous

A small Python toolkit for cryptographically signing data so you can trust it hasn't been tampered with when it comes back from an untrusted client.

3,134
BSD 3
Used by 15
40Health
Library PyPI

aiosqlite

Async/await-friendly wrapper around Python's built-in sqlite3 module for asyncio applications.

1,575
MIT
Used by 15
76Health
Library PyPI

croniter

Parses cron schedule strings and iterates the matching datetime values, with DST, second/year fields, and last-weekday support.

563
MIT
Used by 15
77Health
Library PyPI

structlog

Structured, typed logging for Python built on plain functions and dictionaries instead of a bespoke logging DSL.

4,951
Other
Used by 14
92Health
Library PyPI

networkx

Python library for creating, manipulating, and analyzing complex networks and graphs.

17,258
BSD 3
Used by 13

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