It supposed to be a rather short tutorial, but no.
Sometimes you want to make a perfect seamless video, without any jumps between last and the first frame, when you watch it on repeat. And it can be tricky to make everything seamless, if you have a network with several different time-related CHOPs or a GLSL shader with several uTime and other dynamic variables. So, here is my approach to make perfect loops like this, or this, or that one.
Mostly it's Pattern + Lookup CHOPs, but I share different tips & tricks along the way of explaining the topic.