He has asked to not reveal it and not likely to reveal it. I asked him about it because I think the press would be insane, but it's a niche B2B SaaS and he doesn't want the "made with AI" branding to hurt the image of the product from a customer perspective. Second concern is people trying to hack it in case the LLM took shortcuts on security.
But I can say that as a 20yr+ eng. and having worked with him on a prior startup, I'm super, super impressed how far he got by himself in under 4 months. Basically a full-blown industry specific CRM with Stripe integration, OCR from mobile web app, desktop web app, marketplace. He himself is concerned that it's the end of SaaS as he thinks anyone can build these things now, but I think there's still a bit of a chasm when it comes to some ancillary pieces like databases.