From whiteboard to code: mapping Facts, Rules, and Premises to OTP processes

This post (Part 2 of 12) explains how the Notification-Oriented Paradigm (PON) maps Facts, Rules, and Premises onto OTP building blocks in Elixir—GenServers for facts, a partitioned Registry as a pub-sub bus, and ETS for fast reads. Facts compare old and new values before dispatching notifications, preventing unnecessary fan-out, while duplicate-key Registry semantics allow multiple rules and premises to subscribe to a single fact name.