In Castle, I used to do the following to register types from a different assembly:
Classes.FromAssemblyNamed(\"MyServer.DAL\")
.Where(type => type.Name
You can use the As's predicate overload!
You can get the all of the interfaces with GetInterfaces from the given types that ends with "Repository" and then select the first interface which they implement and register it.
var assembly = Assembly.GetExecutingAssembly();
ContainerBuilder builder = new ContainerBuilder();
builder.RegisterAssemblyTypes(assembly)
.Where(t => t.Name.EndsWith("Repository"))
.As(t => t.GetInterfaces()[0]);