A Fastify backend (the Business OS Core API) runs the DAPA orchestrator and a provider-agnostic Model Router spanning Anthropic, OpenAI, Gemini, DeepSeek, and local Ollama, routing directives to AI employee adapters behind an approval gate and an immutable audit log; a Next.js 15 CEO Dashboard provides the command-center UI, including live executive-summary KPIs/charts and a chat interface grounded in live operational data.