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

91Health
Framework PyPI

django-rest-framework

The most widely-used toolkit for building Web APIs on top of Django, with serializers, viewsets, and a built-in browsable API.

30,191
BSD 3
Used by 15
98Health
SDK PyPI

Azure Identity (Python)

Microsoft Entra ID token authentication for Azure SDK clients in Python

5,609
MIT
Used by 15
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.

3,135
BSD 3
Used by 15
40Health
Library PyPI

aiosqlite

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

1,576
MIT
Used by 15
83Health
Library PyPI

markdown-it-py

A CommonMark-compliant Markdown parser for Python, ported from the JS markdown-it

1,370
MIT
Used by 15
76Health
Library npm

node-html-parser

A very fast HTML parser that builds a lightweight DOM tree with full CSS3 selector support.

1,246
MIT
Used by 15
77Health
Library PyPI

croniter

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

562
MIT
Used by 15
88Health
Framework PyPI

FastMCP

The fast, Pythonic framework for building Model Context Protocol servers, clients, and apps

27,913
Apache 2.0
Used by 14
91Health
Framework PyPI

Pydantic AI

A type-safe Python agent framework built by the Pydantic team

20,217
MIT
Used by 14
92Health
Library PyPI

networkx

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

17,292
BSD 3
Used by 14
66Health
Library npm

mathjs

Extensive math library for JavaScript and Node.js with big numbers, complex numbers, units, and matrices.

15,078
Apache 2.0
Used by 14
46Health
Library Go

jsoniter

A high-performance, 100% compatible drop-in replacement for Go's encoding/json.

13,866
MIT
Used by 14
76Health
Library PyPI

structlog

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

4,965
Other
Used by 14
63Health
Library npm

@apidevtools/swagger-parser

Parses, validates, and dereferences Swagger 2.0 and OpenAPI 3.x specs in Node.js and browsers

1,210
MIT
Used by 14
89Health
Library npm

@xmldom/xmldom

A pure JavaScript, W3C-standard DOMParser and XMLSerializer for parsing and building XML/HTML documents

469
MIT
Used by 14
79Health
Library PyPI

prometheus-client

The official Python instrumentation library for exposing Prometheus metrics

4,375
Apache 2.0
Used by 13
96Health
SDK PyPI

Slack SDK for Python

The official Python SDK for building apps, bots, and integrations on the Slack Platform.

4,016
MIT
Used by 13
67Health
Library npm

colord

A tiny, dependency-free TypeScript library for parsing, converting, and manipulating colors in any format.

1,891
MIT
Used by 13
64Health
Library npm

node-sql-parser

Parses SQL statements into an AST and converts them back to SQL across a dozen database dialects.

1,042
Apache 2.0
Used by 13
92Health
SDK PyPI

clickhouse-connect

ClickHouse's official high-performance Python driver, with native Pandas, NumPy, PyArrow, and Superset support

522
Apache 2.0
Used by 13
39Health
Library PyPI

sniffio

A tiny Python library that detects which async framework (trio, asyncio, or curio) your code is currently running under.

153
Other
Used by 13
90Health
SDK PyPI

E2B

Python SDK for spinning up secure, isolated cloud sandboxes where AI agents can safely run code.

13,989
MIT
Used by 12
91Health
Library PyPI

PyMuPDF

A high-performance Python library for extracting, rendering, converting, and manipulating PDF and other document formats.

10,792
AGPL 3.0
Used by 12
77Health
Library PyPI

APScheduler

Python task scheduler with cron, interval, and one-off triggers, backed by pluggable persistent datastores for distributed job scheduling.

7,637
MIT
Used by 12

Join founders buildingwith open source

Opinionated takes, migration guides, cost-saving tips, and insights from the open source ecosystem.

Subscribe on Substack
Join 750+ subscribers