aico-backend-implement

Execute backend implementation with TDD (Test-Driven Development). Write failing test first, then implement, verify each step. Use this skill when: - User asks to "implement this backend task", "implement backend" - Have an implementation plan ready and need to execute it - Executing steps from /backend.plan output - User says "start coding backend", "write backend code" - User asks to "use TDD", "write test first", "test-driven" for backend code - Fixing backend bugs (write failing test that reproduces bug first) TDD Iron Law: NO PRODUCTION CODE WITHOUT A FAILING TEST FIRST TDD Cycle: RED (write failing test) → Verify fails → GREEN (minimal code) → Verify passes → REFACTOR Prerequisites: - MUST have task file in docs/reference/backend/tasks/ (use /backend.tasks first if not exists) - MUST read constraints.md before writing any code. Flow: Check Task File → Read Constraints → TDD Cycle (RED→GREEN→REFACTOR) → Verify Each → Run All Tests → Update Task Status → Notify PM