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

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
39Health
Library npm

json-schema

A lightweight, historical CommonJS implementation of the original JSON Schema draft specifications

530
Other
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
51Health
Library npm

ExcelJS

Read, manipulate, and write XLSX spreadsheet data, styles, and formulas in JavaScript

15,486
MIT
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
83Health
Tool npm

openapi-ts

OpenAPI-to-TypeScript code generator producing production-grade SDKs, Zod schemas, and TanStack Query hooks.

5,450
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
51Health
Library npm

JSON-Patch

Lean, high-performance RFC 6902 JSON Patch and JSON Pointer implementation for applying, generating, validating, and observing diffs between JSON documents.

1,982
MIT
Used by 14
54Health
SDK Composer

league/flysystem-aws-s3-v3

The official AWS S3 v3 SDK adapter for PHP Flysystem's unified filesystem API.

1,657
MIT
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
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
81Health
Library npm

JSONPath

A JavaScript library for querying, transforming, and extracting data from JSON documents using an extended JSONPath syntax.

1,158
MIT
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
80Health
Library PyPI

opencv-python

Pre-built, pip-installable OpenCV bindings that give Python programs full computer vision and image-processing capabilities without compiling from source.

5,412
MIT
Used by 12
88Health
Library Composer

Symfony Yaml

PHP component for parsing and dumping YAML files, used throughout the Symfony framework

3,837
MIT
Used by 12
79Health
SDK npm

@e2b/code-interpreter

JavaScript/TypeScript SDK for running AI-generated code in stateful, isolated E2B cloud sandboxes

2,415
Apache 2.0
Used by 12
90Health
Library PyPI

PEFT

Hugging Face's library of state-of-the-art parameter-efficient fine-tuning methods for large models.

21,730
Apache 2.0
Used by 11

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