I can't really blame them for nondeterministic builds. Not only was Java slower but computers in general were slower when javac was written, so recompiling unch

I can't really blame them for nondeterministic builds. Not only was Java slower but computers in general were slower when javac was written, so recompiling unchanged source files was an obvious waste that everyone tried to avoid (by checking mtimes, because hashing every file was also pretty expensive).