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

87Health
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
84Health
Tool PyPI

mypy

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

20,640
MIT
Used by 30
45Health
Library npm

zod-to-json-schema

Converts Zod validation schemas into standard JSON Schema, ready for OpenAPI, OpenAI, and JSON Schema draft 7 consumers.

1,252
Other
Used by 30
90Health
Library PyPI

websockets

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

5,717
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
45Health
Library npm

JSON5

JSON for humans: an extended JSON syntax with comments, trailing commas, and unquoted keys for hand-written config.

7,162
MIT
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
90Health
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.

19,983
MIT
Used by 26
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
91Health
Library PyPI

jsonschema

The reference implementation of JSON Schema validation for Python, supporting every draft from 3 to 2020-12.

4,980
MIT
Used by 26
89Health
Tool PyPI

Alembic

Database migrations tool for SQLAlchemy with autogenerate and transactional DDL

4,393
MIT
Used by 26
91Health
Framework npm

Fastify

A fast and low-overhead web framework for Node.js, built around schema-based validation and a plugin architecture

37,137
MIT
Used by 25
97Health
SDK PyPI

sentry-sdk

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

2,202
MIT
Used by 25
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
60Health
Library Go

gjson

Fast, dependency-light JSON value extraction for Go using dot-notation paths.

15,558
MIT
Used by 22
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
92Health
Framework PyPI

LangChain

The most widely adopted Python framework for building LLM-powered agents and applications

146,323
MIT
Used by 21
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

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