An idea to resolve incompatibility of DataMemberAttribute.Order's lower bound between msgpack and protobuf.

ProtoBufCompatIdea.cs

// Initialize SerializationContext, which can be singleton.
var context = new SerializationContext();

// Set compatibility option, which set array lower bounds to 1 instead of 0.
context.CompatibilityOptions.OneDataMemberLowerBound = true;

// Following is as is...
var serializer = MessagePackSerializer.Create<Foo>( context );
using( var stream = new MemoryStream() )
{
    serializer.PackTo( stream, foo );
    // Assume Foo is:
    // class Foo { [DataMember(Order = 1)]int Bar = 1; }
 
    // stream should be { 0x91, 0x1 } instead of { 0x92, 0xC0, 0x1 }
}