Another thing though: If at least one of your constraints are speed, a dynamically language probably shouldn’t be your first choice. If you need to maintain memory safety, Java or Rust would be more applicable.

That being said, once you have a codebase written in a certain language, you might just be stuck there due to hired talent being familiar with it. I don’t think I’ve really seen a company pull off a polygot move cheaply. Instead, a parallel move to something like Crystal may require minimal re-training.

… just thoughts I would have if I were in charge of investing R&D time at a large org like the ones mentioned in the article.