> I've tried builing locally with the following command, and I get something that suggests there may be a problem, but I'm not sure where to go from here. > > $ ./pre-inst-env guix build --no-grafts --rounds=2 --check ruby > > guix build: error: build failed: derivation `/gnu/store/37rb11ivy4w6ydn0px386k158ixbgczz-ruby-2.5.1.drv' may not be deterministic Not sure if I am the best person to ask, but I generally build it once, copy the store directory to /tmp, delete it from the store with "gc", then build it again. Finally, compare the two directory trees - I use "meld" (don't think this is in Guix, unfortunately), but others use "diffoscope", as I understand. HTH, ben