Artefact — Memory in two layers · Engram and Headroom

Status: stub. A redacted session handoff and a before-and-after context measurement land in Phase 7.

What the artefact is

Engram is local-first storage for curated summaries, decisions, prompts and session handoffs in SQLite, so a conversation can be resumed in any project; it is integrated with JEV for fast compaction. Headroom is token control: it strips, cleanses and analyses code and logs before they reach the model, compressing rather than truncating.

What it proves

Two distinct problems recognised as two — persistence and window economy — instead of one tool asked to do both.

When it is delivered

Phase 7. Both tools are part of Sam’s own workflow; they are deliberately not part of the public assistant, which is stateless by decision (see reference/decisions.md D11).