struct MyViewModel: ViewModel {
    // thanks to protocol composition we define only the services we want to use
    typealias Services = HasService1 & HasService2
    init(withServices services: Services) {
        services.service1.executeService1()
        services.service2.executeService2()
    }
}

struct MyOtherViewModel: ViewModel {
    typealias Services = HasService2 & HasService3
    init(withServices services: Services) {
        services.service2.executeService2()
        services.service3.executeService3()
    }
}