for each module that fails its regression tests on $current did it fail identically on $previous? if yes, "SEP" else work out why it failed (a bisect is useful for this) attempt to group failure causes for each failure cause is that a regression? if yes, figure out how to fix it (more code? revert the code that broke it) else (presumably) it's relying on something un-or-under-documented should the existing behaviour stay? yes - goto "regression" no - note it in perldelta as a significant bugfix (also, try to inform the module's author)