This year I'm solving problems in C.
I've been backfiling gaps in my computer science knowledge this past year and I've been inspired to program much closer to the machine's hardware.
The goal for this year is not to finish all 25 days (although that would be a nice bonus) but to better learn how a computer works. Not having the level of abstraction I'm used to should prove to be quite challenging but I'm ready for it.
Merry Christmas!