Given that CIDER (or clojure-mode) inserts the ns bits in every new Clojure file, this seems doable.

indeed :) perhaps someone has packaged it already

Found this link - https://emacs.stackexchange.com/questions/45629/template-for-new-file

looks tasty! particularly as I already use yasnippet, thanks 🍻

And doom emacs has a file-templates module that uses yasnippet.

You can check what they are doing in that module.

Here is the link to it - https://github.com/hlissner/doom-emacs/tree/develop/modules/editor/file-templates

Why create new shell files instead of babashka? 🙃

https://www.emacswiki.org/emacs/AutoInsertMode