What problem does it solve? Non-trivial code changes often ship with unclear plans, untested fixes, and undetected regressions. This Skill enforces a disciplined sequential pipeline—setup, planning, test-driven implementation, multi-axis review, and simplification—so every change is validated at explicit exit gates before commit. ## Core Features & Use Cases - Parallel Multi-Agent Planning: Synthesizes implementation plans via three parallel planning agents, or adopts a supplied plan file, with mandatory root-cause analysis for bug fixes. - TDD Implementation with Per-Phase Commits: Runs RED-GREEN-REFACTOR cycles on a faster model, committing scoped changes at each phase exit gate. - Deep Multi-Axis Review: Dispatches fresh-context review subagents across correctness, security, architecture, and lifecycle axes, including shared-state consumer tracing. - Use Case: When fixing a regression whose root cause is unknown, the pipeline forces an evidence-backed root-cause analysis, a reproduction test, and a full review before any commit lands. ## Quick Start Use the dev-cycle skill to implement this change through the full plan, implement, review, and simplify pipeline.