I don't know if they build and work, but I'd suspect they do, based on the refactorings being discussed. The commits seem to be clicking along. A diffstat of roughly where I think they branched off of ntp vs. master takes a moment to poke through, because the raw stats are "1032 files changed, 126489 insertions(+), 143789 deletions(-)", but there's a lot of trading C code for test code and more docs in there.
I don't know exactly what metric you're using but this doesn't match my "obvious lack of progress".