I understand your reluctance to use Java, but it's actually pretty good if the developers use small libraries instead of the giant frameworks most Java servers use... a Java server for this kind of stuff will run within 200MB+ comfortably and with very high performance when written properly. Anything using 3GB for this stuff is doing something terribly wrong.
Yeah I know, nothing except maybe the JIT that requires java programs to use more memory than Go, but in practice Java apps are almost always significantly worse.
C# is also pretty bad, but not quite as bad I think.
I can only assume it's a cultural thing since reflection and abstraction is used so much.
Rust apps are always nice since they are generally <20MB or something.
