We should look into making it so we can do replacements without needing source files. Similarly, it should be possible to build overlays without having built arm9 code as well.
Somehow I didn't realize this sooner, but we've already solved this issue (really simply, too) in Serial Loops. I'll port that solution to the main package instead.
We should look into making it so we can do replacements without needing source files. Similarly, it should be possible to build overlays without having built arm9 code as well.