Hi Greg, for the purposes of GNU Guix, #:parallel-build? and #:parallel-tests? are distinct flags and the latter (if implemented) would apply to the check phase. Our cmake-build-system in this case defers to gnu-build- system, which ought to insert -jN as you described.
It could be that the package(s) you build have disabled parallel tests for some reason (breakage, reproducibility, ...). If not there would be issues passing those arguments, which I don't believe the case from static analysis however. Cheers, Liliana
