I'm still early on in the series but does Casey ever go over from the ground up how he swapped to 4coder? I know he has his own config but wasn't sure if at any point he showed how he set it up from the very start.

There were a few streams (I believed called "4coder Fridays") but I don't know if they are on youtube. But either way, those are for older versions of 4coder so they would probably not help much.

The getting started article in the 4coder forums might help you: https://4coder.handmade.network/forums/articles

Note that 4coder is now open source and not maintained by the original author (Allen Webster), and I don't know if there is a place where user patches are published. The best way to find out or get some help is probably to join the 4coder discord server.

Is it still something worth looking into now that it's publicly maintained? The getting started link is over 2 years old and I imagine a good amount changed in that time.

I was able to follow along with the link a week ago and everything I tried still held up (custom hooks and highlighting mainly)

The API hasn't changed much in the last few releases, it was mostly bug fixes, so the article should still be mostly on point. Note that other persons may have a different way to do things, and it's worth looking at Ryan Fleury's custom layer as it's widely used and tested and get help on the 4coder discord server.

I can't say if it's worth it to get into it now. I've been using 4coder for several years and got accustomed to several of its features and features I added myself so it would be hard for me to move to another editor. And as long as there aren't massive issues, I don't really have a reason to. I haven't spent any time yet to find out if the community has decided on a place to get updates.

If there are customization that you really need and can't get in another editor, than 4coder might be a good choice if you have the time to do it yourself.

Maybe try it for a month to see if it fits.