Tabby is a self-hosted, open-source AI coding assistant that runs locally via Docker, offering code completions and codebase-aware chat similar to GitHub Copilot — but with full data privacy, no subscriptions, and offline capability. It supports team features like SSO, RBAC, and audit logs, and integrates with VS Code. The tradeoff: setup requires more effort than cloud tools, and completion quality depends on the local model and available hardware. Best suited for privacy-conscious developers, regulated environments, or teams wanting to own their AI infrastructure rather than rent it.