StructureMap singleton usage (A class implementing two interface)

Question

You can use the Forward<,>() registration to tell StructureMap to resolve a type using the resolution of a different type. This should do what you expect:

ObjectFactory.Initialize(x =>
{
    x.For<IInterface1>().Singleton().Use<MyClass>();
    x.Forward<IInterface1, IInterface2>();
});

I would register the MyClass itself and then pull that out of the context for the Use statements of the individual interfaces.

ForSingletonOf<MyClass>().Use<MyClass>();

For<IInterface1>().Use(ctx => ctx.GetInstance<MyClass>());
For<IInterface2>().Use(ctx => ctx.GetInstance<MyClass>());

Try looking at the different overloads to Use, especially Func overload. From there you can tell how StructureMap should create your instance with another object already registred.