This rule, against rewriting code in a different language, has become obsolete. It's important to understand why. Historically we rewrote code by hand, which inevitably introduced bugs. And we weren't very rigorous about writing the regression tests that should have smoked out the bugs after translation. Today, we have robot friends to do our code rewriting for us. And, if we have any trace of a freaking clue, we have already written regression tests with excellent coverage. Under these circumstances, an automated rewrite in order to collect performance gains or memory safety can be a good thing to do. Generally speaking, these days, if I have to do major surgery on one of my projects in Python or C, I will enlist a robot friend to lift the code to either Go or Rust. This has never failed to be a functional improvement.