What problem does it solve? It guides the implementation of Módulo 3 of the EOS academic project: enforcing user roles in an Express/Supabase backend and building the specialist registration flow with license verification status in the React Native app. ## Core Features & Use Cases - Role Enforcement: Extends JWT authentication to attach the user's role and adds a requireRole middleware that rejects unauthorized requests with a 403 ApiError. - Specialist Registration: Implements a backend module (routes, controller, service, repository) with multipart upload of DNI and title photos to the specialist-docs bucket, duplicate license detection, and pending license status. - Frontend Flow: Adds a conditional specialist registration path, a specialist status screen showing pending/rejected/verified states, and role-based navigation. - Use Case: A student building the EOS app uses this Skill to implement the complete M3 deliverable, including Spanish-language Jest tests for duplicate licenses, uploads, and role middleware, while keeping the integration contract stable for M4 and M5. ## Quick Start Use this skill to implement Módulo 3 role enforcement and specialist registration for the EOS project on branch feature/e2-roles-specialist-register.