[[!comment format=mdwn username="joey" subject="""comment 2""" date="2016-06-20T18:36:07Z" content=""" Here's another, perhaps simpler way to do it. The `adjustPropertySatisfy` function takes an existing Property and applies a function to the Propellor action inside it. adjustPropertySatisfy :: Property metatypes -> (Propellor Result -> Propellor Result) -> Property metatypes So, given the `genrsa` Property from my example above, you could modify its action to use withUmask: adjustPropertySatisfy genrsa (withUmask filemode) This is simpler, but less flexible since it causes the entire Propellor action to be run with the specified umask, not just part of the action. But it works well for your purpose I think. """]]