I am (very) slowly working on that one to work with compiler tracer. I can push my branch (I thought it is pushed) where I am trying to implement such and if you have any PR then it will be more than welcome.

The compiler gives you a warning for unreachable functions. That means private functions which are not called in the module where these are defined are throwing such warnings. But public functions that are never called anywhere are not checked by the compiler.

It doesn’t look like your mix unused project you referred to here was ever posted to this thread. Here’s a link to the project:

The problem with these approaches is that quite a lot of dynamic invocation (:erlang.apply/3) happens in Erlang/Elixir projects and dialyser/xref and friends can’t be aware of what’s being invoked when the call site is dynamic.

This will return a lot of false positives due to macros and other autogenerated functions in Elixir.