Codex has a web interface that hosts little virtual machine environments, you give it access to a git repo and then you can approve it's pull requests and test them locally, and roll back crappy code...
It's a little weird to setup at first but pretty nice.
If they weren't helping the military autonomously kill people I'd keep using it, but I don't want to make it stronger.
You could also run your own virtual machines to let other ai fuck around in so it doesn't escape whatever root you give it.