Poetry has a similar thing with poetry shell that launches your current shell but with a (poetry-managed) virtual env activated.

For more ideas, see also Nix's nix-shell (spawn shell from nix file) and nix shell (spawn shell from cli args)

Also strongly suggesting it should be mise en .

I think this would be fairly easy to implement if anyone wants to have at it, I think we can just call Exec::run() from a new CLI command with "$SHELL" after changing the current directory

I like the idea. When using it from Xcode project scripts it'd just be one line of code. I'd check if it works fine with sandbox-env, which is the tool that Xcode uses to sandbox the execution of the script.

I'm not Xcode developers will entirely understand what the command is for, but the copy and pasting that they'll most likely do has more chances to work.

Have you considered mise shell? As someone not familiar with rvm in, I wouldn't be able to guess what the command is for.

well, we already have a command mise shell. It's a bit different though in that it only works inside of a session where mise activate has already been executed.
I thought for a bit maybe we could merge the 2 and have mise shell do the same thing as mise en if it's not inside of a mise activate session, but I think they work so differently that it makes more sense to have separate commands.

Naming is hard 😬. I'd expect mise shell to take the role of mise en, and the current mise shell to be more like mise load/set to mean that a tool is being loaded into the activated session.