http://www.arclanguage.org says "Arc is fluid and future releases are guaranteed to break all your code." As a result the community tends not to care about compatibility either. Anarki has numerous little incompatibilities. Since literally anybody can commit to it at any time it's hard to make any assumptions about it whatsoever.
All of us choose to live in one repo; either arc3.1 or anarki or something of our own. My personal set of favorite incompatibilities is at http://github.com/akkartik/arc, for example. My recommendation: jumping back and forth between arc3.1 and anarki is more trouble than it's worth.
I had to gradually accustom myself to how things work here. Even now I monitor new commits to anarki as I pull them. It can't be like a library you blindly rely on.
You're welcome! One of the great benefits of this model is that it is literally frictionless to propose new ideas. I hope you will feel free to make your own edits directly to anarki. I'd love to see you post about them here if the rationale isn't obvious, but it's always ok to make changes first and see if anybody complains :)