Spandex 2.4.0 has been released, adding support for function decorators to easily create traces and spans based on function calls.

For example:

defmodule MyThing do
  @decorate span()
  def do_something_complicated(arg1, arg2) do
    # ...
  end
end

This will generate a span called MyThing.do_something_complicated/2 that reports how long the function took to execute and reports errors that are raised.

https://github.com/spandex-project/spandex/releases/tag/v2.4.0