This guide explains the machinery behind the speed, in plain terms, for anyone trying to read the US financial market clearly. How C++ quantitative finance works with memoryThe second piece is control over memory. They use specialized hardware to process market data, and they write C++ that works closely with that hardware. The 2024 Stack Overflow Developer Survey shows C++ holding steady as the language of choice where that speed is needed. Firms replay years of historical market data through a strategy to see how it would have behaved, a process called back-testing.