IMO, using something like Python or JavaScript is a good idea if any of the following criteria is met:

- Working with data more than executing other binaries

- Dominant data processing path is structured (e.g. JSON, XML, binary)

- Script requires complex flow control to be manageable (e.g. functions, if, case)

- Shell UI requirements that involve handling command-line options

- You find yourself going _deep_ into the docs for jq to get the job done

.

Conversely, BASH is better under the following circumstances:

- Orchestrating other binaries the majority of the time

- Simple jobs that work with newline-separated text lines, or all data can be comfortably "stringly typed"

- Launching and job control for other processes

- You just need to glue some other shell commands and binaries together

- Are just manipulating shell environment vars, or providing a custom user shell (e.g. Python venv `activate`)

- Need to wrap a CLI tool in a simple way

.

The minute you have to reach for BASH arrays, case statements, math... stop everything and seriously consider using a language that has stronger support for all that.

Since you’re the only other person in this thread to mention it, I’m surprised the industry has been sleeping so hard on QuickJS as a scripting language runtime.

I think the lack of batteries-included stdlib is probably the biggest holdup, but JS can be much nicer than python for anything that can be decomposed into map/reduce/filter string munging.