epics — the story backbone
The story backbone — the resolution that enables mapping
Backbones are the artifact that makes the next phases possible. They are deliberately small. One sentence each. Recognisable as scenes within the activity, not yet detailed enough to estimate, design, or test. "Gal calculates a 28-student MCQ scoring." Not "As a teacher I want to..." One sentence, in the voice of the person doing the activity.
Backbones are cheap to write and cheap to throw away. A backbone that turns out to be the wrong scene gets deleted. One that turns out to be two scenes gets split. The cheapness is the point — backbones haven't yet acquired the weight of wireframes, schemas, or scenarios.
When two Epics should be one — and when one should be two
Two adjacent friction columns sometimes describe a single activity from two angles. The journey says calculates and enters and marks in two columns; in Gal's actual workflow these are interleaved — she switches between them many times in the same session. Two Epics here would create artificial coordination overhead. One Epic — "Gal calculates and marks in a single view" — is closer to the activity as lived.
The opposite happens too. A single column on the journey turns out to contain two distinct activities. Submits looked like one phase in Gal's brief. In the kickoff it became clear: submitting to the school system involves the school admin's side, which the team has not yet observed; confirming receipt for Gal can be built now. One column, two Epics. The school-admin Epic is deferred.
The test: does the activity have a single start, a single end, and a person who experiences it as one thing? If yes, one Epic. If no, two.
Resolution gate — Epics to Shaping
Enough to begin shaping.
Each Epic has its name, description, what-done-means, and a complete first set of backbones. Backbones are written in the voice of the person, not the system.
Test: a stakeholder reading only the Epic name and the backbones can recognise what the activity contains and roughly what work is implied.