I'm currently in the process* of a cleanup of the process package to reduce the usage of CPP conditionals in the code. Currently, as Simon PJ pointed out, it's quite difficult to follow the logic between Windows and POSIX platforms. During the cleanup, I've noticed that: 1. There's also quite a bit of complication around the __GLASGOW_HASKELL__ conditionals, intended to make the package compilable with other compilers 2. There seems to be no way that - in its current state - the package could be compilable with a compiler besides GHC I wanted to reach out and see if anyone is currently using the process package on a compiler besides GHC, and if so, get information on whether recent releases also work, and get some kind of automated testing in place to prevent regressions. If there are no such users, I'm likely to remove the (presumably non-working) conditionals. * No pun intend