Demo.Store = BI.inherit(Fix.VM, { computed: { b: function () { return this.model.name + 1 }, c: function () { return this.model.name + this.model.b } }, methods: { run: function () { this.model.name = 2; } } }); var model = new Fix.Observer({ name: 1, arr: [{ n: 'a' }, { n: 'b' }] }).model; Demo.Fix = BI.inherit(BI.Widget, { _store: function () { return new Demo.Store(model); }, watch: { b: function () { debugger; } }, mounted: function () { this.store.run() } }); BI.shortcut("demo.fix", Demo.Fix);