It’s great when a development system allows this! Ink, Dialog, and Inform 7 are the three IF systems I know that support it—that is, they let you edit your source, hit a button, and have the game update, without losing your progress. I don’t think there’s a way to do that with ZIL yet.
(For Inform, you have to specifically hit “replay” rather than “run”. For Dialog, you need to use the interactive debugger dgdebug rather than dialogc. For Ink, you have to use the Inky editor.)