The underlying need is to traverse and update data structures, so language designers went with universally mutable objects with arbitrary references. That makes

The underlying need is to traverse and update data structures, so language designers went with universally mutable objects with arbitrary references. That makes the representation of an individual object quite simple, and it does centralize the complexity of memory management in garbage collection, so it's a good engineering decision. But real GC requires extensive tuning (different "generations", stop-the-world pauses, etc) and that's simply not an elegant solution. My approach was to revisit that underlying need, and I settled on a data model that simply prohibits cyclic data structures, so memory management doesn't have to be more complex than reference counting. Now, I'm still going to have to implement zippers and paths and such to handle traversal, but I think that will still be far cleaner. I have some notes here if you're curious: https://tenet-lang.org/types.html https://tenet-lang.org/types.html