You can “patch” the code of a module by decompiling it into Erlang Abstract Format, then do any changes and then recompile the module. You can also namespace it this way.
I implemented it here: punkix/lib/punkix/patcher.ex at master · Zurga/punkix · GitHub
Example usage is here: punkix/lib/mix/tasks/punkix/gen.live.ex at master · Zurga/punkix · GitHub
