Yes, the detection is definitely an important part of it that I've idly thought about, but haven't written anything about. The proposal is still very early, an

Yes, the detection is definitely an important part of it that I've idly thought about, but haven't written anything about. The proposal is still very early, and not implemented anywhere. The Github wiki is open to edit if you want to write up a proposal (on a new page) and discuss it on https://oilshell.zulipchat.com/ https://oilshell.zulipchat.com/ . A prototype is even better. Although I think that perhaps running the binary with `-h` or `--help` and an env variable like SHELLAC_FEATURE_DETECT=1 might be a more backward compatible detection mechanism. If the binary doesn't support shellac, then it will probably exit quickly with help, or an error message. (And shells could cache this detection info.) If it does support Shellac, then it will print some kind of "spec" to stdout describing where the completion is. Is it in the binary itself written in Rust/Python/etc., or is it in a separate completion script ? The conversation has been dormant lately, but like I said I think there are a few groups of people motivated to do this (e.g. alternative shell users who don't want to rewrite completions themselves).