My jewellery SaaS already runs on Next.js for the frontend and Node.js for the backend. What I now need is a seamless, first-party WhatsApp Business integration—no third-party BSPs such as MSG91 or AiSensy—using Meta’s own Cloud API. Scope • Set up the WhatsApp Cloud API under my Meta Business account, including the proper phone number verification and webhook configuration. • Register and get approved two categories of message templates: utility (for bills/invoices) and marketing (for promotions). All template copy and designs are ready; you only handle their submission and approval. • Build the Node.js endpoints that my existing backend will call: – /api/whatsapp/sendInvoice – /api/whatsapp/sendPromotion Each should accept a payload with the customer’s WhatsApp number, template variables, and an optional media URL, then send the message through the Cloud API and return the delivery status. • Add minimal authentication so these endpoints are secure for my internal services. • Provide concise README or inline comments showing how to rotate tokens, add new templates, and monitor delivery reports. Acceptance criteria 1. Invoices and promotions arrive on a live WhatsApp number using the approved templates with variable substitution working. 2. The endpoints return Meta’s message ID plus a clear success/error flag. 3. Setup instructions allow me to re-deploy or migrate without additional support. If you have recent experience wiring Node.js backends to the WhatsApp Cloud API and can demonstrate at least one live implementation, let’s talk.