Odysseus is a self-hosted, full-stack AI assistant platform built with FastAPI (Python) and vanilla JavaScript. It provides a unified workspace for chat with multiple LLM providers (OpenAI, Anthropic, Ollama, local models), deep research with multi-step web analysis, RAG-based memory and document indexing, email/calendar/contacts management via IMAP/CalDAV/CardDAV, an image editor with layers and AI tools, task scheduling, web search, and MCP (Model Context Protocol) server integration. The architecture follows a modular route-per-domain pattern with backward-compatibility shims, a shared SQLite database via SQLAlchemy, and ChromaDB for vector storage. The frontend is a single-page application with streaming markdown rendering, live thinking display, and extensive keyboard shortcuts. The system is designed for multi-user operation with owner-scoped data isolation, atomic file writes for state persistence, and comprehensive security measures including SSRF protection, prompt injection hardening, and secret encryption. It includes a hardware-fit recommendation engine (cookbook) for selecting optimal LLM inference backends (llama.cpp, vLLM, diffusers) based on local GPU capabilities. While primarily an application, it incorporates significant data engineering patterns: embedding lanes with fallback, search result ranking, memory consolidation with near-duplicate removal, and deep research synthesis pipelines. The codebase demonstrates strong engineering practices with extensive regression testing (over 400 test files), CI/CD pipelines, and security scanning. However, it shows signs of technical drift with duplicate code paths (e.g., search ranking in both `src/search` and `services/search`), heavy monkeypatching in tests, and some legacy migration complexity. The project is actively maintained with frequent commits and issue triage.