This repository is a comprehensive, async-first CLI application for downloading content from Douyin (TikTok China) without watermarks. It also powers a desktop application (Douzy) via a shared Python backend and offers an optional FastAPI REST server. The architecture follows a modular design: URL parsing dispatches to concrete downloader classes (video, music, live, user, mix) via a factory pattern; user-mode downloads employ a strategy pattern for posts, likes, mixes, and collections. Heavy emphasis is placed on anti-bot circumvention—X-Bogus and A-Bogus signature generation, browser fallback via Playwright, and risk-control retry logic—reflecting the adversarial nature of Douyin's API. The codebase is well-structured with distinct layers (auth, config, core, storage, control, utils) and extensive test coverage (>80 test modules). It demonstrates strong engineering practices: async I/O throughout (aiohttp, aiosqlite, aiofiles), configurable concurrency with rate limiting and retry backoff, incremental downloads via disk and database checks, structured progress reporting, and manifest logging. However, the project shows signs of technical drift: some dependencies are out of sync between requirements.txt and pyproject.toml, bundled msToken configuration may become stale, and the desktop-sidecar integration introduces coupling risks. Despite these, the code is actively maintained and functionally robust for its specific domain.