With respect to Hubris, the build badge was, in turns out, pointing to a stale workflow. (That is, the build was succeeding, but the build badge was busted.) This comment has been immortalized in the fix.[0]
With respect to Humility, I am going to resist the temptation of pointing out why one of those directories has a different nomenclature with respect to its delimiter -- and just leave it at this: if you really want to find some filthy code in Humility, you can do much, much better than that!
https://github.com/oxidecomputer/hubris
And, that one underscore-delimited folder name in this repo just catches the eye, huh?
https://github.com/oxidecomputer/humility