Comment #2 on issue 415 by allber...@gmail.com: xmonad assumes that the shell can find it in $PATH http://code.google.com/p/xmonad/issues/detail?id=415 I find it useful to be able to rename my xmonad for testing, when I have reason to expect that my development will break it (I have a wrapper script that does xmonad-test || xmonad, so I can killall xmonad from a console and get the working one). The standard way to deal with this is to look at argv[0], and use it as is if it contains slashes or do a PATH search on it otherwise. This is difficult in Haskell because getProgName trims everything to the basename "for portability reasons" --- but there is also an additional complication, whose resolution also fixes this problem. The complication is that, when xmonad exec()s a customized xmonad, it needs to pass on the path it was invoked by so that mod-q does the right thing even if the user chooses to delete their xmonad.hs. But if you need to do this, then the solution to the other problem is obvious: use a wrapper which uses the same option to pass its argv[0] (or shell $0) to the real xmonad. (That is, xmonad exec()s xmonad-bin exec()s user xmonad-platform.) There are a couple of additional considerations here; in particular that the user xmonad binary needs to use the original (base)name instead of a hardcoded "xmonad" and therefore its xmonad.hs should also use that basename (so it would be e.g. xmonad-test.hs). (The wrapper might also check for $(basename $0)-bin and fall back to xmonad-bin, and even run xmonad-bin if the custom one exits with an error/signal, thereby making it do the same kind of debugging setup I described above.)