Sure. I'm also thinking, how do they trust my server? With photographs it makes sense - A server that can tamper with photos live is not sci-fi, but it's also

Sure. I'm also thinking, how do they trust my server? With photographs it makes sense - A server that can tamper with photos live is not sci-fi, but it's also just a little bit expensive. In my case I want to notarize text. What if I store "evil message" in my database and publish "good message" to the PNL? Unless the end recipient of "evil message" is also logging to the PNL, (Which is hard, they're supposed to be a dumb client) nobody will ever contradict the server. I could round-trip the messages through the PNL. Make the recipient pull them from there instead of the server. But that sounds like extra risk. It's a tricky problem, and in the end I'll have to cut lots of corners for convenience. That makes me sad.