note that bookmarks don't float, unlike git branches, so if your pattern is to produce a lot of commits, you'll want something to keep your jj bookmarks pointing to the top of your pile of commits.
this is less of a problem if you're more into the 1 change == 1 commit workflow.
There's an experimental-advance-branches feature which helps with that!
There's a very common alias `jj tug` for this case:
It moves the nearest bookmark to the commit before the current one (which should be your working commit).