Leg model and rig to follow along to this tutorial:
https://youtu.be/BnUGyq5i1Eg
Contains the constraint examples, leg model fully rigged, as well as a leg that only has deforming bones.
I'm making this free, so people can follow along more easily, if you appreciate it and find value in this, please donating when you download. Thanks.
This was made with Blender 2.92