Stop in for a cup of coffee

I am kind of building as I go trying to utilize scraps from framing the house. My design and creative influences are directly correlated to my scrap pile! I want to do some kind of top track only and have it so that the “back end“ never escapes the pocket, thereby eliminating the need for a bottom track. I want it to recess completely so I will need to engineer some kind of widget to pull the door closed. I have some scrap UHMW I can rip for guides inside the pocket. I may do some kind of removable access door for the rail system? The whole concept is still fresh as I just made the decision last night with some single malt creativit!