With Unity, Avalonia/Uno Platform, ASP.NET Core, NativeAOT and compact self-contained trimmed JIT deployments, the sheer cross-platform, cross-workload and depl

With Unity, Avalonia/Uno Platform, ASP.NET Core, NativeAOT and compact self-contained trimmed JIT deployments, the sheer cross-platform, cross-workload and deployment flexibility proposition of C# far surpasses Java even if we count in JVM + Kotlin for additional points of the latter. Now let's talk performance of most commonly used web frameworks. I will save you the trouble of reading long text. Just check https://www.techempower.com/benchmarks/#section=data-r21&test=composite https://www.techempower.com/benchmarks/#section=data-r21&tes... and search the tabs for the more popular Java frameworks like Spring, Spark, Struts, Grails, Wicket, etc. You may find yourself surprised, finding most of them in the bottom 25th percentile. Now scroll back to the top of the page and check where ASP.NET Core is. That's right, more often than not, in the top 10. All that performance, and you get it out of box just by using defaults and then some more. The only exception I see is Vert.X which is both mentioned across the web and also present in the top of the list. Now, you may say that it's not very representative and there are entries of dubious usefulness in production scenarios (looking at you Just.js). And you would be right. However, the way to get most performance from ASP.NET Core is not by using tricks but rather simply writing code like in Node.js with app.MapGet("/users", delegate) and friends. Despite all this, I still think JVM technologies like Hotspot or GraalVM have an upper hand over what .NET JIT/NAOT is capable of. However, keep in mind the out-of-ordinary performance gains that C# gets with each subsequent release. In areas with significant possibility of improvement like arm64 codegen quality, moving from .NET 6 to upcoming .NET 7 will yield you up to 40% performance improvement from JIT alone. And it was done in significant part by changing the code of JIT/Runtime that used to be x86_64-first to being cross-platform oriented (e.g. Vector codepaths becoming plat-agnostic, correct atomics being emitted for ARM, etc.). .NET Framework used to be stagnant. After becoming OSS, .NET is the polar opposite, getting significant improvements in all of its areas with each release be it runtime code, standard library, language features or supported usage scenarios. I think today, C# and .NET are mostly being held back by decades of legacy libraries and decisions, which you may consider avoiding in favor of newer solutions, regardless if those are in BCL or community-driven libraries. Still, sometimes people simply use code in such a way that unreasonably kills its performance. But as long as you avoid known gotchas, your C# code will easily perform in production at the speed of Rust, C++ or C.