I did write a Scoop manifest for something of mine a long time ago. I don’t know much about it but remember that it was pretty straightforward json, and Scoop supported some common installers (at least msi & innosetup). Perhaps that could be an option for you if you’re lucky the erlang & elixir install packages are fairly standard. It’s a bit of a rabbit hole to have to go down, but might be worth considering if nothing better crops up.
