First, I wanted to thank everybody involved for the great book and this forum. This is truly amazing experience to build something really complex from just a handful of zeros and ones. I just finished building ALU and wanted some advice about its design. I read on the forum that if your implementation passes the test, you shouldn't bother, but when I discovered forum after making all chips from chapter 1 I understand that some parts could be built in much fewer lines of code. And that's not just different implementation, that's different kind of thinking - much more laconic and elegant. So I rebuilt everything in order to make good habits from the beginning. Now I built an ALU and it passes the test. I tried my best, but I think that something could be missed. Can I ask to review my ALU and help me with some suggestions how can I make it better? Thanks.