Thanks, it’s late here now but I’ll try to look soon. I didn’t realize significant improvements over Goldberg etc al were really possible. I’ll try to understand that too.

Is there another post somewhere giving a general description of what you are doing?

Do you have a link about your messaging app? And PIR doesn’t conceal the existence of traffic, so it doesn’t seem like the right thing for messaging. It’s more for databases as the name implies. What exactly are you trying to do?