Addition Module:
Since the last version I have fixed a bug involving carrying on of the bits. I have also increased the speed by quite a bit.

It features a pin to indicate when an integer overflow has occured

Subtraction Module:
Since the last version I have fixed some bugs however, it still cannot tell if the output is positive or not.

Randomness Module:
This module outputs either 1 or 0 when it recieves input, it only requires 1 bit to give an output

All 3 use a pin system so that you can remove them and replace them with a better version of them without affecting the rest of your ALU.

I have colour coded each section and used signs to make it easy to modify.