But whenever people talk about writing Bash, you always have someone advocating that you should write POSIX sh instead if you want maximum portability. To paraphrase Qui-Gon Jinn, "there's always a more portable language."

Underlying all of these discussions is an attempt to reduce issues of portability to 0. It's a good goal, but IMO interpreted languages will by-definition never be the solution.

I've started reaching for Go in situations in which I'd usually reach for Bash or Python, and it's a godsend, because I can control for portability at compile time. If you make compiling for various GOOS and GOARCH targets the norm, portability is never an issue again.