On: Time for Makefiles to Make a Comeback

[oso2k]

Easy enough (assuming $SRC is your list of source files and 'all' is top level target) 'make watch' could do this

   watch:
        while ! inotifywait -e modify $(SRC) ; do time -p make all; done

[lloeki → oso2k]

If you care for it, fswatch is cross-platform:

https://github.com/emcrisostomo/fswatch