I have been working with Elm regularly since about 0.13, so I'm fairly competent up to and including JSON, Cmd, Sub, JS interop and topics like that. I have built some fairly detailed apps with those technologies included. I focus on educational software.
What are the minimum extra skills I need to learn to create true multi-user apps, with log-in forms, authentication, and personalised student learning records?
Does this require a considerable leap in what I have to know, or are there relatively painless ways of getting to this next level?
Thanks in advance.