Every quant developer knows the feeling: you write an algorithmic strategy, run it against a basic backtesting script, and the equity curve looks like a flawless, vertical rocket ship. You feel like a market genius. But then you deploy that exact same strategy against a high-fidelity system—or live capital—and it immediately bleeds money. What happened? The strategy worked perfectly on paper because paper lacked friction. In Series 1 of this architectural deep dive, we pulled back the curtain on