How do you deal with changes to multiple files at the same time? What if a subset of users see updated file A but not file B? You don't have such things in oth

How do you deal with changes to multiple files at the same time? What if a subset of users see updated file A but not file B? You don't have such things in other languages simply because they have not been initially created as glorified templating engines. More importantly: for example, Django in debugging mode allows you to swap templates on the fly, so is with the executable code. Except nobody does it because that's considered ridiculous.