I agree, a huge driver for me leaving the Java ecosystem for Go was the JVM. Maybe Kotlin native can address that, but despite what people in the Java world seem to believe, the JVM is a big disadvantage.
The JVM may be full of technology that’s indistinguishable from magic, but deployment is a pain in the ass.
Maybe things have changed in the last few years but - having to ship a huge file tree alongside the actual binary (or binaries because JARs are also a nightmare), and the slow startup time due to the need to interpret/compile bytecode instead of just running machine code, make Java really unpleasant to use in many common use cases.
Well I shipped fat jars using capsule more than 15 years ago without any issues. Nobody ships file-trees.
Also the Startup depends on how much memory you allocate, but much of it is due to verifying class security, a feature that other runtimes don't even have. Or badly used reflection, another feature others don't have.
In any case I really never found it an issue if a server takes 3 seconds to start and I never understood why people complained about Java startup. My guess is they complain about clunky desktop application with a million classes written in it.
Regarding the bytecode: the interpretation and just in time recompilation gives Java sometimes better than native performance.
It also allows you to hook into the code on the fly and transform it with agents. Can native do that?
The file tree I was referring to is the JRE, not the code.
In any case, if Java works for you then that’s great. I’m just relating my own experience, where I found that the need for a JVM was less of a blessing than a curse.
As a former C developer who has been using Java for 20+ years, moving to Go was like lifting a weight off my shoulders. (I suspect I’d have felt the same with Rust, Swift or any other modern AOT language). It’s so refreshing to just have a binary, and be able to execute it, and not worry about a pile of irrelevant external factors.
