Building a constraint programming solver in Julia

This is an ongoing series about: How to build a constraint solver? If you haven't read this post: Perfect as it is part 1;) More than 2 years ago I wrote a Sudoku solver in Python. I really enjoyed it and therefore I've spend some time to do the same in Julia just faster;) Then I wanted to build a whole constraint-programming solver in Julia. Well I actually still want to do it. It will be hard but fun.