Lessons from Building Multiple Crypto Systems Simultaneously

Building multiple complex systems at the same time teaches you what actually matters. Here's what I learned from shipping Caos House, Caos Engine, and TradeTab in parallel. ## The Challenge When you're building three systems simultaneously, you can't afford to over-engineer. Every decision has to be justified by immediate need, not future possibilities. ## Key Decisions **1. Shared infrastructure where it makes sense** We built shared components for authentication, payment processing, and API patterns. But we kept each system's core logic separate. This gave us speed without coupling. **2. Database per system** Each system has its own database. This might seem wasteful, but it allowed us to: - Scale independently - Deploy without affecting other systems - Make schema changes without coordination **3. API-first from day one** Even if we didn't need an API immediately, we built everything as if we would. This made integration between systems trivial later. ## What I'd Do Differently **Start with one system, then extract patterns** Instead of building three systems from scratch, I'd build one completely, identify the patterns, then extract them for reuse. This would have saved time and reduced complexity. **More testing earlier** When you're moving fast, it's tempting to skip tests. But technical debt compounds faster when you're building multiple systems. Write tests from day one. ## The Result We shipped all three systems. They're in production and serving real users. But the process taught me that building multiple systems simultaneously is a tradeoff—you gain speed but lose focus. Sometimes that's worth it, sometimes it's not.