public Repository(Class1 class1, Class1 class2)
{
    _class1 = class1;
    _class2 = class2;
}

builder.Register(ctx => new Class1()).Named<Class1>("a");

builder.Register(ctx => new Class1()).Named<Class1>("b");

builder.RegisterType<Repository>().WithParameters(new[]
{
    new ResolvedParameter((p, c) => p.Name == "a", (p, c) => c.ResolveNamed<Class1>("a")),
    new ResolvedParameter((p, c) => p.Name == "b", (p, c) => c.ResolveNamed<Class1>("b"))
}).AsImplementedInterfaces();