Currently there is no way to see the progress of compiling a module. GHC HEAD provides a callback mechanism to report the warnings and errors for each module. If this callback is called, we know it has been recompiled. (Maybe it would be good, if the GHC API would call a callback also before compiling a module.)

The interesting question is: how to provide this interface on the Scion side? For Haskell clients a simple callback should be fine, but for servers this requires bidirectional computation instead of simple "evaluate this on the server" calls. Hm..