How to debug ExUnit tests with :debugger?

I have the idea to use the (Erlang) debugger to debug my Elixir tests, using breakpoints set via the UI and stepping through code by line or expression. I also want to avoid littering the code with Pry or breakpoint statements. Is that something that’s possible?

I searched docs and more broadly, but I didn’t find a conclusive answer yet.

My understanding for now is, that the debugger needs to be started from the iex repl, but there doesn’t seem to be reliable way to run tests from there.