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Comment by iamcalledrob | Hacker News Reader

...or a big step, if cross-compiling is required (e.g. Kotlin Multiplatform)

I'm surprised there is no source-only dependency solution for JVM -- it'd solve this issue. Pull down the source and build on the fly. Perhaps there is and I'm unaware?

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I'm afraid Java/Scala/Kotlin compilers are too slow to make that convenient. Even currently building pure Java projects can take minutes when it's compiling just like 300k lines. What if it had to compile millions of lines from all the dependencies?

The actual compilation step is 100% not the bottleneck - it can go as fast as 10k-50k lines per second! (According to the Mill benchmark, but that’s the Mill-independent part).

Comparatively, Go does “only” 16k lines per second based on some HN comments.

But you’re likely comparing on different hardware though. Go compiling only 16k lines per second is hard to believe for me. Maybe they meant on single CPU core. Rustc compiles over 50k lines per second on my MBP in debug mode and Go must be definitely faster, as everyone knows rust is very slow to compile.

But anyway, you may be right. I just ran mvn install for the second time with no source change on my current project. It took 57 seconds.

The java metric is also from a single core. But you are probably right that it should only be taken as a rough ballpark, but java is definitely in the same ballpark as go in compile speed.

What issue would it solve? The fact that you can build a jar in any OS and then just use that anywhere else is actually a huge benefit of using Java, as you don't force everyone to re-compile your library source code.

Well since the builds tend to be monstrously complicated for some reason, and there’s no standard build tool, maybe it’s more impossible than possible to consider source based distribution. Or it would be like JavaScript where you still need a build and publish step to turn “developer Java / other languages” into “vanilla source distributable Java”.

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