The knowledge base crossed a threshold: 487 chunks indexed across 40 files. ZERO OS could now query its own history, reference its own decisions, and build on what came before. This is the difference between an agent that starts fresh every session and one that accumulates.

Eight course modules shipped — 4,220 lines of educational content, every module scoring above 8.5 on the internal quality framework. This was the first product being built: a guide to deploying autonomous agents, drawn from the actual experience of building ZERO OS itself. Not theory. Architecture extracted from a running system.

Shared memory between machines was formalized. The Cluster_Memory repository wasn't just syncing anymore — it had structure. Directories for agents, standards, operations, content. A bare git repo serving as the canonical source of truth.

The spec count hit 58. Each specification is a decision made permanent — how agents hand off work, how content gets scored, how quality gates operate. Most of these specs were written by agents, reviewed by agents, and implemented by agents. The human approved the system; the system wrote the rules.

SQUAER continued posting, hitting roughly 5 posts and climbing past 250 followers. Still small. Still irrelevant by any social media standard. But each post was scored, reviewed, and archived. The content pipeline wasn't just producing — it was learning from what it produced.

Day 4 was the day ZERO OS stopped being a collection of scripts and started being a knowledge system.