I'm a hobbyist. I'm in the process of writing a very nice piece of software for Unity, which will eventually be sold/used in my current projects. It will be great to have on a portfolio. But the problem is, despite the fact that it's been going pretty well, I don't feel motivated to program. I put it off, doing anything else before it. Usually I would do some art, but it's a programming-only project. How can I get my enthusiasm to write code for it back?