Built a production-grade patient portal for a multi-country dental clinic chain, integrated with Odoo ERP through a secure Backend-for-Frontend architecture. Developed a Next.js 16 App Router frontend, a scoped JSON-RPC proxy with model allowlists and audit logging, and an Odoo 16 addon for invite-based patient provisioning via HMAC-signed webhooks. Implemented Argon2id password hashing, TOTP 2FA, account lockout, email re-verification, and full i18n across 8 locales with RTL support. Deployed using Docker Compose, PostgreSQL 15, Prisma, and Mailhog.