ClientID: "raptors", KindID: "door-open", Email: true, }) builder.Add(models.Preference{ ClientID: "raptors", KindID: "feeding-time", Email: false, }) builder.Add(models.Preference{ ClientID: "dogs", KindID: "barking", Email: true, }) preferences, err := builder.ToPreferences() if err != nil { panic(err) } Expect(len(preferences)).To(Equal(3)) Expect(preferences).To(ContainElement(models.Preference{ ClientID: "raptors", KindID: "door-open", Email: true, })) Expect(preferences).To(ContainElement(models.Preference{ ClientID: "raptors", KindID: "feeding-time", Email: false, }))