POSIX compliance has never brought me any issues, if I want bash syntax I just use `bash -c COMMAND`. You can invoke bash scripts with `bash SCRIPT` or just add

POSIX compliance has never brought me any issues, if I want bash syntax I just use `bash -c COMMAND`. You can invoke bash scripts with `bash SCRIPT` or just add the bash shebang `#!/bin/bash` to the top of your script, set the executable bit and invoke directly.