     option = valueAccessor().option
 
     try
-      ab_tests = window.CircleABTestVM.ab_tests()
+      ab_tests = AB
 
       display_p = ab_tests[test] is option
 

    i = randInt(options.length)
    @set_option(test_name, options[i])

window.CircleABTestVM = new ABTestViewModel

ko.bindingHandlers.ab_test =
  init: (el, valueAccessor) =>

class ABTestViewModel
  constructor: () ->
    # defs don't need to be an observable, but we may want to do
    # inference in the future. Better to set it up now.
    @test_definitions = ko.observable(_ab_test_definitions)

    # @ab_tests is an object with format {'test_name': "chosen_option", ...}
    # Again, no need to be observable yet
    @ab_tests = ko.observable({})

    @setup_tests()
