how do I use it with autojump?
https://github.com/junegunn/fzf/wiki/examples#autojump
You'll have to comment out the j() function in /usr/share/autojump/autojump.sh
You have to parse it to extract the directories without all the metadata it spits out.
Then you probably need to write a shell function in your preferred shell to tie the pieces together, as well as assign it to a keybinding. It's not too hard.
I use xonsh for my shell, so my config probably won't help. And doing it in xonsh is probably a lot messier than doing it in Bash.