priyanshscpp/Cpp-High-Frequency-Trading-System-HFT ? reverse-engineered prompt

Build me a C++ trading backend for crypto derivatives that can connect to Deribit and place, cancel, and modify orders with very low latency.

I want it to feel like a real high performance trading system, with a simple command line interface, real time market data updates, basic risk checks, and support for spot, futures, and options. It should have both REST and WebSocket based communication, keep state for orders and positions, and be designed so the critical path is as fast as possible.

Please include a clean structure for the trading engine, market data handling, order management, and risk management, plus a small latency test setup so I can see how it performs. Use modern C++ and make it robust enough to handle reconnects and heavy order flow. If you need to look up current Deribit API details or best practices, go ahead and check the latest docs online.