Is this project still active?

Hi!
I'm completely noob to OCI.
While looking for a way to test container runtimes, I came across this tool. Thank you!

I wonder if this project is still active.
I heard that runC is the reference implemenation for OCI runtime spec, but running this tool against runC still has not-ok testcases.

Is this implementation bug in runC? or due to the outdated this tool?
Or is there something I don't catch?