Feature implementation from PRD with iterative testing

★ 6.9 · vibe-coding

dev4-implement is a Claude Code skill that implements a feature from its PRD, writing clean, well-structured code to Google staff-engineer standards and verifying each step iteratively. It reads `.llm/<feature>/prd.md`, `design.md`, and `tmp_exploration.md` to gather full context, then checks whether a git worktree exists and creates one with `wt switch -c feat/<name>` if needed. A step-by-step implementation plan is written to `tmp_impl_plan.md`; every step is kept small enough to test independently, with failures fixed before moving on. The built-in style guide enforces functions under 20–30 lines, no debug logs, logic grouping, and explanatory inline comments. After all steps pass, the full test suite runs and the skill hands off automatically to `/dev5-review`, making it the fourth stage of the structured `/dev` workflow.