Our biggest win in 2025: reducing AI decision latency from 2-3 seconds to under 500ms in Arvo, our AI personal trainer. What drove it: Moving from a single monolithic AI call to 19 specialized micro-agents that run in parallel. Each agent handles one specific task (load calculation, exercise selection, injury detection), and they communicate through a lightweight orchestration layer. The impact: Users now get real-time suggestions between sets instead of waiting. Engagement metrics improved 3x because the AI finally felt "instant" rather than "loading..."