Concrete Without Forms - YouTube
https://www.youtube.com/watch?v=nkxe9uK8jSo&t=30s

That really is a prototype for 3d printing buildings.

That was filmed near me.  Urschel Labs is still going strong although they focus on industrial/commercial food cutting/ making machines now, the founders were always inventors making machines to automate a process so this printer does not surprise me.  Family still owns the company.