Develop using thin vertical slices
Context
We want short feedback loops when building features. If an idea takes days of backend and frontend work before you can see it running, that's too long to find out it doesn't feel right. This is also a useful rule for LLM agents to follow — build a minimal working version across the full stack first, then iterate.
Decision
Build features as thin vertical slices — minimal end-to-end from UI through GraphQL through business logic through database.
Start from the user-facing side and work inward. Get to something you can see and interact with quickly, then do another pass to improve it. Don't abstract until patterns emerge across multiple features.
Consequences
Ideas get validated early. You sometimes build things rough on the first pass, but that's cheaper than discovering the approach doesn't work after a week of polished code.