Of course, we can assign to context a a symbol that points to context b to create nested contexts, but it gets mucky from there when you want to access context b from outside context a, so we can wrap it in a function:
(cond
((null? tree) (throw-error "List expected in @get."))
((>= (length tree) 2)
(if (> (length tree) 2)
(@ (cons (context (tree 0) (name (tree 1))) (2 tree)))
(context (tree 0) (name (tree 1)))))))
(context 'bar "test" "test value")
(context 'foo "child-hash" 'bar)
(println (@ '(foo child-hash test))) ; => test value
I think we should be able to go as deep as we want this this, although I only tried it a few levels down.