Well, a second call to "make" with unmodified source on a local system has the same resulting output because make knows how to avoid rebuilding output files whe

Well, a second call to "make" with unmodified source on a local system has the same resulting output because make knows how to avoid rebuilding output files when the source hasn't changed since the last build. The goal of reproducible/deterministic builds is typically to be able to produce the same output files without already having that output. (That's because the people interested in reproducible/deterministic builds are usually trying to prove something about the relationship between the source and the build output. Make doesn't really do that -- the only thing it can prove is that the mod times of output files are later than the mod times of the source files they depend on, according to the make file.) So, yes, make is typically deterministic in a general sense (given a good makefile and certain assumptions that are pretty reasonable in the context of a developer doing development on a local machine). But isn't what people are looking for from reproducible/deterministic builds.