What problem does it solve? Design teams often make opinion-based decisions without testing whether changes actually produce desired outcomes. This Skill structures design decisions as testable hypotheses using Jeff Gothelf and Josh Seiden's Lean UX methodology, enabling evidence-based iteration through Build-Measure-Learn cycles for tiny teams of 1-5 people. ## Core Features & Use Cases - Hypothesis-Driven Design: Structures design decisions in the canonical Lean UX format (outcome, users, change, evidence) with ICE scoring (Impact, Confidence, Ease) for prioritization. - Assumption Mapping: Places assumptions into a 4-quadrant risk/knowledge framework (Q1-Q4) with category classification (Value, Usability, Feasibility) and movement tracking across cycles. - MVP Experiment Design: Selects from 7 experiment types (A/B test, fake door, concierge MVP, Wizard of Oz, paper prototype, smoke test, one-question survey) with measurable success criteria. - Validated Learning Log: Documents completed cycles with evidence, VALIDATED/INVALIDATED results, and pivot/persevere/kill decisions. - Use Case: A product team redesigning a checkout flow uses this Skill to generate a hypothesis backlog, map riskiest assumptions, design a fake door test, and document validated learning before handing results to HEART Metrics measurement. ## Quick Start Ask the /user-experience skill to help you test whether a design change will improve conversion, and the ux-orchestrator will route the request to this Lean UX facilitator.
