taskbash

Install

Do nothing.

Write run script

printf '#!/bin/bash\n\nhello() {\n  echo hello!\n}\n\n"$@"' > run
chmod +x run

Use run script

$ ./run hello
hello!

Why?

It's like https://github.com/go-task/task, but without YAML and Go. (Nothing wrong about Go as a language, but runner script should have zero dependencies of its own, if possible.)