Your comment is half right. While your app is JIT compiled, the runtime and its libraries are AOT compiled using a technology called cross-gen. As others have p

Your comment is half right. While your app is JIT compiled, the runtime and its libraries are AOT compiled using a technology called cross-gen. As others have pointed out, the .NET team has a NativeAOT experiment (previously called CoreRT) that lets you AOT compile your entire app. Also, Java takes longer to reach steady state as it starts execution in an interpreter, then JIT compiles hot methods. .NET skips the interpreter and goes straight to JIT compilation.