Sending iMessage Mini-App Payloads from macOS

Sending iMessage Mini-App Payloads from macOS I have been super excited by the stuff the guys at Photon have been doing with iMessages. They kind of nerd-sniped me with their launch letting you programmatically send custom mini-apps. Basically, they let you send arbitrary web content via their helper iMessage app extension. I believe they also support sending custom payloads for any iMessage mini-app. Their helper app extension Spectrum makes it so you don't need to worry about needing to setup your own app extension, instead you just need to send the web payload. These notes are just to scratch my own reverse-engineering itch to figure out how Photon/Spectrum works. I would not use this for production — just use their API and services. While editing this post, I noticed Linq has also launched a similar service. tl;dr The interesting part is inside Messages.app's private ChatKit stack: MSMessage -> CKBrowserItemPayload / IMPluginPayload -> CKComposition -> IMMessage -> CKConversation…