The `gh stack` CLI sounds essential for people using git, but I hope it doesn't become required, as people using things like jj/sl should be able to work with stacks. `gs submit`/`gs push` being the interface is fine, but `gs init` and `gs add` should be optional.

They confirmed below that you should be able to use this with jj just fine, just like you can already use gh to create a PR that you've authored with jj: https://news.ycombinator.com/item?id=47759426