I need an experienced full-stack partner to build the very first release of a multi-tenant WhatsApp Automation platform that talks directly to Meta’s official WhatsApp Business Cloud API. This is a full SaaS, not a single-tenant script, so clean, scalable architecture and production-ready code are non-negotiable. Scope and core modules • WhatsApp Cloud API integration that handles session management, webhooks, templates and media. • A no-code, drag-and-drop chatbot flow builder (React Flow) that lets non-technical users design conversation paths. • Broadcast engine for bulk messaging with queueing (Redis) and smart retries. • WhatsApp Marketing CRM — contact management, lead scoring, analytics & reporting with campaign management, automated follow-ups, plus segmentation and targeting baked in. • Embeddable chat widget that visitors can launch from any website. • Multi-tenant data isolation, role-based access and JWT authentication. Tech stack Backend: Node.js with TypeScript, Express or Fastify, PostgreSQL, Redis. Frontend: React or Next.js with TailwindCSS and React Flow. Infra: AWS or DigitalOcean, CI/CD, secrets management via environment variables. Key expectations 1. Codebase organised for future feature expansion (micro-service friendly). 2. Clean TypeScript typings, ESLint/Prettier in place. 3. Proper testing strategy (unit + minimal integration). 4. Dockerised containers and IaC scripts for easy deployment. 5. Detailed README and basic admin guide. Acceptance criteria • All modules above functional in a single live environment. • Onboarding flow allows a new tenant to sign up, connect a WhatsApp Business number and start broadcasting. • Load test shows stable performance for the first 1 000 concurrent conversations. • Source code passes review and unit tests >90 % coverage. When replying, briefly outline a high-level architecture, any similar SaaS you’ve shipped, and your proposed timeline to reach an MVP we can demo to early adopters.