User Stories
Definition
A user story is a simple narrative of a single requirement told from the user’s perspective. It is not meant to capture the complete requirement — it is a placeholder for a future conversation that demonstrates value to a user and encourages collaboration.
Core Ideas
Anatomy
As a <role> (type of user)
I want <goal>
So that <benefit>
Plus acceptance criteria. A story has three parts: title/situation; the “As a / I want / So that” description; and acceptance criteria.
Acceptance criteria
Conditions that must be met, expressed clearly and unambiguously. Judge them by: specificity, whether the solution meets the requirement, relevance, testability, and whether it can be put into practice successfully.
INVEST
Good stories are Independent, Negotiable, Valuable, Estimable, Small, Testable.
Level of detail — the Cloud/Kite/Sea/Fish/Clam model
Alistair Cockburn’s altitude metaphor: keep stories “at the waterline” (sea level) — not so high they’re vague (cloud/kite) nor so low they drown in detail (fish/clam).
Why user stories
User-centric focus, communication and collaboration, iterative development, flexibility, and easier estimation and planning.
Relationships
- Business Analysis — user stories are a core requirements-modeling tool
- Use Case and Swim Lane Diagrams — complementary, more structured views of process flow
- Scrum — stories populate the product backlog
- Agile — stories embody just-enough, conversation-driven requirements