Hi Maxime! > I'd make this > > (lambda* (#:key tests? #:allow-other-keys) > (when tests? > [do-stuff])) > > That way, the package transformation --without-tests=bitmask > should work. (Try "guix build --without-tests=bitmask bitmask".) Ah I forgot about this, thanks for reminding me. :) Regards, RG.