Asia/Kolkata
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ProjectsJanuary 15, 2024

WhatsApp Cloud API Platform

Hashir Hameed Niazi

Overview

Owned end-to-end development of a full-stack WhatsApp Cloud API platform at Telecrm, enabling businesses to communicate with their leads at scale through WhatsApp. The platform supports one-on-one messaging, bulk campaigns, interactive messages, and automation workflows.

Key Features

  • Interactive Messaging: Implemented WhatsApp Cloud API interactive messages including WhatsApp Lists, allowing users to send, view, and update interactive content through one-on-one messaging or automations.
  • Conversation Analytics: Built a comprehensive analytics dashboard where users can view sent messages, cost incurred, and categorical representation of message types sent.
  • Real-time Chat UI: Developed the WhatsApp messaging interface supporting text, audio, video, document-based messages, and interactive messages. Built a rich text editor with bold, italic, strikethrough support, template-based shortcuts, and drag-drop media upload with captions.
  • Campaign Dashboard: Created a bulk messaging campaign system capable of sending to 100K+ leads (scaled from 5K), with delivery stats, error code breakdowns, scheduled retries with undo capability, and granular tracking of sent/delivered/read metrics.
  • Template Management: Built a template selector modal with filtering by language and category, along with full template creation, updation, and management UI.
  • Contact Filtering: Added the ability to filter WhatsApp contacts by lead assignee, status, unread chats, and search by name or phone number.
  • Embedded Signup: Built WhatsApp Cloud API embedded signup flow for direct user onboarding.
  • OTP Integration: Created WhatsApp OTP integrations enabling users to send OTP to leads via WhatsApp Cloud API.
  • Location Messages: Added support for sending location messages through the WhatsApp UI.
  • Permissions System: Implemented granular permissions for WhatsApp-based features.
  • Mobile App: Implemented all WhatsApp features for the mobile application as well.

Technologies Used

  • Node.js / Express.js: Backend API and webhook processing
  • Angular: Frontend application and chat UI
  • MongoDB / Atlas Search: Lead data storage and search
  • Redis: Caching layer for chat performance optimization
  • AWS (SQS, SNS, Lambda, EC2): Queue processing and infrastructure
  • WebSockets: Real-time message delivery

Impact

  • Scaled broadcast capacity from 5,000 to 100,000 leads (20x improvement)
  • Reduced chat load times through multi-layer caching
  • Enabled businesses to manage all WhatsApp communications from a single CRM interface

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