You can fairly easily write helper scripts using eg pkg_util to automatically add profiler decorators (eg with kernprof) so that profiling never requires modify

You can fairly easily write helper scripts using eg pkg_util to automatically add profiler decorators (eg with kernprof) so that profiling never requires modifying code. My team has a large body of profiling code written with kernprof and none of it modifies the underlying source. Profiler annotations are solely added automatically by the little profiler runner tooling we wrote. Not to say other profiling tools aren’t worth it.