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TDD Layer Registry

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Description

This file maps architecture layers to their skills and provides project-level configuration for the outside-in-tdd workflow. Generic agents read this file instead of hardcoding layer definitions.

Installation

This entry records only its repository, not the path inside it, so there is no exact command to give. Open the source below and copy the folder into ~/.claude/skills/, or the file into ~/.claude/agents/.

Repository README

This is the README for JoeGaebel/outside-in-tdd-starter, shared by 2 entries in this directory. It describes the repository, not this entry specifically.

TDD Layer Registry

This file maps architecture layers to their skills and provides project-level configuration for the outside-in-tdd workflow. Generic agents read this file instead of hardcoding layer definitions.

Layers

Layer Testing Skill Implementation Skill Description
e2e cypress-end-to-end-testing Cross-layer E2E verification of business processes
frontend jest-frontend-testing frontend-implementation React components, hooks, pages
backend jest-backend-testing backend-implementation API route handlers, lib utilities

Layer Dependencies

None.

E2E Test Directories

Classification Path
Business process cypress/e2e/business-process/
Infrastructure cypress/e2e/infrastructure/

E2E Failure → Layer Routing

When the E2E test fails, use these indicators to determine which inner layer to target:

E2E Failure Type Target Layer
UI element missing/wrong frontend
UI interaction not working frontend
Page doesn't exist (Next.js 404) frontend
Data not displaying correctly frontend (if rendering) or backend (if API)
API returns wrong data backend
API route doesn't exist (404/405) backend
Business logic incorrect backend
Database state wrong backend

Commands

Purpose Command
Specific test npm run test:unit:spec
Full verification ./t
Lint npm run lint
Typecheck npm run typecheck
Mutation testing npm run test:mutate:uncommitted

Mutation Testing

  • Threshold: 60%
  • Surviving mutants report: reports/mutation/surviving-mutants.txt

Design Constraint Checks

When the TDD planner validates a design approach against the runtime environment, check for these conflicts:

Check Conflict
Browser-only APIs during render? Next.js SSR hydration mismatch
State initializes differently server vs client? React hydration mismatch
Borrowing pattern from e