What Procfile do I need to use when making a Heroku app with Kotlin/JS?

I am very new to web dev, so please dumb things down for me.

Did you search on github using their code search? That’s usually a good ressource for those kind of questions.

I’m not sure what even to search for.

Why do you want to deploy Kotlin/JS app to Heroku? Kotlin/JS applications are static websites, you just need basic web hosting.

I’m using Heroku because it seems like a great service, and if I build more complex stuff, I don’t want to switch.