I've been thinking about getting back into the game but never had any real incentive to (as I no longer run any forums).
I'm happy to discuss funding options.
Some have asked me to reboot the addon for 2.x. If you'd like to see this add-on updated please leave a comment here: https://xenforo.com/community/threads/rebooting-custom-markup-for-user-add-on.178673/
A few years ago I made the original Custom Markup for User add-on. @DarkGizmo has PM'd me asking if I would upgrade the add-on for 2.x.
I was wondering if there's any interest for this add-on still? (In 2020 I think they're rather tacky.) Maybe @IGN Engineering ?
This is pretty much saying "Knowing how to put legos together will get you a lego tower", but yes. XenForo is written in PHP.
You'll also need to know the basics of database administration to interact with the database, and HTML/CSS/JS to write front-end code.
I think if you have to care about what forum software your competitors use, there would be bigger problems you need to pay attention to, such as the content of your forum...
Cookies are stored on client machines and should be considered compromised. (this was my original comment by the way, before I realised I misunderstood things)
Apologies, I removed my last post because I realised I misunderstood your post.
If your WAF can look up XF's datastore then you should be able to look up user info with the `xf_session` cookie, which contains the session ID. How much of a performance penalty I don't know - depends on where you...