React 19, Zustand, a 5-Provider AI Broker, and P2P Multiplayer — How I Architected My Learning Platform

Posted by Prateek | March 2026 I shipped React 19 in production when it was still RC. Not because I love living dangerously — well, maybe a little — but because I was building PatternMaster from scratch and there was no legacy to protect. When you're starting fresh, you pick the best tools available right now, not the ones that were best two years ago. This is the architecture post. Blog 1 covered the overall vision, Blog 2 covered the game mechanics. This one is for the people who want to know how it's actually built — the state management, the AI plumbing, the theme system, the database decisions. Grab a coffee. The Stack (and Why I Made These Choices) Let me be upfront: I didn't pick these tools to flex. I picked them because each one solved a specific problem I had. React 19.2.0 + Vite 7.1.9 — React 19 shipped concurrent features that genuinely matter for an app that's doing heavy AI streaming and 3D rendering simultaneously. The server actions model didn't apply here (Express back