Disclaimer: I love writing production systems in Java. I was a C++ programmer for 10 years before moving to Java about 15 years ago. Java offers a virtually all in one package when writing large systems. You have a single language where you can write code that doesn't care to be the fastest possible, and you just rely on ZGC to do its thing, and it works. Or you can write GC free code with a mostly quite performant SoA type approach. You can do this in the same codebase, and developers don't need to know different languages to write either style of code. You then have one build system, one deployment system, an incredible set of observability tooling, etc, etc.
So I might be biased, but with the correct curation of AGENTS.md files and skills, we're getting extremely good results using Claude Code writing Java.
Another disclaimer: I haven't tried with another language, but we're happy with the results.
Would be interesting to find out what kind of production systems you write in Java and how you deploy / scale them. What DB backends you use, caching, etc. And whether you're also on Spring.
Always finance, trading systems. In the last 15 years mostly what they call "front office".
At the moment, for the place I work, we deploy on AWS mostly (because that is where our target trading venues often are). DB backends are largely not something we think about too much, because all of that is done out of band of course as a final state. Our main persistence is through our "bus" using aeron, and everything starts and recovers from there. This is not your typical enterprise java. No Spring.
Ok that's quite interesting. Am I correct to presume this is crypto trading? I was under the impression most regular HFT is near the exchanges, or physically at the exchange in a DC. Unless it's an AWS Outpost or something.