epic-maplisted

# Epic map Work larger than one session fails in two ways. Attempted in one run, it exhausts the context somewhere in the middle and leaves a half-finished branch nobody can assess. Decomposed in the human's head each time, it costs the same conversation every session and loses whatever the last session learned. The map is the durable middle. It holds the cut, the open decisions and the accumulated learning; each slice is a session's worth of work that ends in a merged change. ## What a slice is **One slice, one spec, one session.** The constraint is context, not ambition — a slice that needs two sessions was cut too big, and the fix is to cut it again rather than to push through. **Slices are vertical.** Each ends in something observable: a user can do something they could not before, or a system behaves differently in a way you can point at. Horizontal slices — all the types, then all the components, then all the tests — cannot be verified, cannot be shipped, and hide their own incompleteness until the last one lands. The test: can this slice produce a `## Done when` that someone could check? If not, it is a layer, not a slice. **A slice is ready when every decision it depends on is settled.** Not when it is next in the list. ## 1 — Name the destination What is true when this epic is finished, in observable terms. Two or three sentences, written so a session that reads only this line still knows what it is aiming at. Then the boundary: what is explicitly **not** i