The default umask in Pinstripe is 002 (rwxrwxr-x).
While this is fine for the default setting where each user belongs to his
own group, it is less suited for the scenario where each user belongs to
the same group by default. In that case, this umask is fatal security-wise.

I think that the umask 022 (rwxr-xr-x) should be used as the default, as it
is safe in both scenarios.