Rewriting a FIX Engine in C++23: What Got Simpler...

QuickFIX has been around forever. If you've touched FIX protocol in the last 15 years, you've probably used it. It works. It also carries a lot of code that made sense in C++98 but feels heavy now. I wanted to see how far C++23 could take a FIX engine from scratch. Not a full QuickFIX replacement (not yet anyway), but a parser and session layer where I could actually use modern tools. The project ended up at about 5K lines of headers, covers 9 message types, parses an ExecutionReport in ~246 ns.