I currently have the Greek (Polytonic) keyboard layout installed, and it works wonderfully for typing Ancient Greek.
However, I sometimes find myself needing to type the obscure letter digamma (capital Ϝ, lowercase ϝ), which isn't available on this keyboard. Ideally I'd move the final sigma to the Q key, and put digamma on the W.
Is there an easy way to accomplish this? I found this page, but it warns me that it's not updated for current versions of Ubuntu. Moreover, digamma is too obscure to be given a name in
/usr/include/X11/keysymdef.h (though it does have suitable codepoints in Unicode), and I'm not sure what I'd have to recompile if I edited that file.