Question: can zsh run bash scripts?
Answer: Zsh can run most Bourne, POSIX or ksh88 scripts if you put it in the right emulation mode ( emulate sh or emulate ksh ). It doesn't support all features of bash or ksh93. Zsh has most features of bash, but in many cases with a different syntax. The shell you use interactively is irrelevant for any script you have.