ProxyPool is a production-grade proxy pool application that automatically collects free HTTP/HTTPS proxies from over a dozen public sources, validates their availability, and stores them in Redis or SSDB. It provides a Flask RESTful API for consuming proxies (get, pop, all, count, delete) and uses APScheduler for periodic fetching and validation. The architecture is a monolith with two main processes: a scheduler that runs fetch/check cycles and an API server (Flask with Gunicorn on Linux). The codebase demonstrates strong software engineering practices: a plugin-based fetcher system with dynamic module loading and caching, a clean Proxy data model with JSON serialization, a decorator-based validator registration pattern, and a layered test suite (unit, API, integration) with fakeredis mocking. External dependencies include Redis/SSDB, APScheduler, Flask, requests, and lxml. The project is actively maintained with recent commits and a comprehensive test suite.