Quickly jumping forward and backward in code (say for testing speed comparison or finding where an error was introduced) is convenient using jj:
jj prev # go back 1
jj prev 3 # go back 3
jj next # go forward 1
jj next 2 # go forward 2
Caveat: I have edit mode set to default (jj config set --user ui.movement.edit true) so I don't need to toss the -e flag in those commands.