Build Log

OS Gate Cleanup

June 22, 2026

The Session-Close Gate was real. The 'pin' gremlin was not. Both now resolved.

EngineOS

files changed

phantom category eliminated

phantom deferrals discharged

new gate added (Session-Close Gate)

Timeline

Start

Three concerns from Zeb's review

Session-Close Gate machinery, escape hatch shape, Demo & Narration aging

Investigate

Read build-session.mjs — gate already existed

Warning-based, not hard-fail. Intentional for historical retros.

Root cause

Found the 'pin' gremlin

substring 'pin' matching 'mapping', 'spinning', 'spin triage' — all three spins miscategorized

Done

Four targeted fixes shipped

Escape hatch, category rename, phantom deferral discharge, build:trends clean

What shipped

Session-Close Gate added to gates.md with escape hatch documented

Escape hatch upgraded: session_close_gate_exempt (bare boolean, deprecated) → session_close_gate.human_accepted + reason (leaves fingerprints)

Deploy Gate trigger narrowed to first deploy / env+config+schema+integration changes only

AI Route Gate trigger clarified: content-based (SDK imports, model/prompt/streaming), not path-based

KNOWN TRAPS Session arc row updated to point to the new gate

ignition.md Deploy orientation line updated to match narrowed trigger

Trigger Map wired: 'Close the session' now routes through Session-Close Gate first

SPIN_CATEGORIES 'Demo & Narration' replaced with 'Session Closure Integrity' and precision keywords

CATEGORY_GATE_MAP entry added for 'Session Closure Integrity' → Session-Close Gate

Two phantom 'Demo & Narration' deferrals (both spin_ids: []) discharged via LEGACY_DISCHARGED_KEYS with audit trail

build:trends runs clean — Demo & Narration gone, Session Closure Integrity shows the one real spin

“The 'pin' gremlin hid in 'mapping.' A substring gremlin is the most polite kind of data corruption — it never crashes, it just quietly lies.”
— Session observation