Senior AI Full-Stack Developer – Node.js, Firebase & WhatsApp Integration

Senior Full-Stack Developer / AI Automation Engineer – KCC AIVA Platform About the Project We are the owners of KCC (Kahan Construction Co.), an established construction business in India. We have an existing AI-powered business management and automation platform called "KCC AIVA", currently under development and deployed in a Google Cloud Run staging environment. We are looking for an experienced Senior Full-Stack Developer or a small professional software development team to audit, stabilize, complete, optimize and deliver our existing platform as a production-ready business automation system. Important: This is an existing project. We are NOT looking to build a completely new system from scratch. Current Technology Stack - Node.js and JavaScript - Firebase Firestore - Google Cloud Run - OpenAI API and AI Agent Architecture - WhatsApp Business Cloud API - Zoho Books API - REST APIs and Webhooks - Document AI and OCR - GitHub and automated testing Existing Business Modules The platform includes multiple business modules: 1. AI Brain, Intent Detection and Request Routing. 2. Labour Management and Employee Records. 3. Attendance, Overtime, Salary and Advance(Kharchi) Management. 4. Project Management and Project Expenses. 5. DPR, Petty Cash and Site Operations. 6. Supplier, Vendor and Customer Management. 7. Document AI, Invoice Extraction and Processing. 8. Zoho Books Integration. 9. WhatsApp AI Assistant and Contact Management. 10. User Authentication, Roles and Permissions. Several modules have already been implemented and tested. We need a complete assessment of the current implementation before making changes. Scope of Work – Milestone Based Phase 1 – Complete Technical Audit - Review the complete existing source code and architecture. - Inspect all modules, services, APIs and integrations. - Review Firestore database structure and security rules. - Identify bugs, incomplete functionality and duplicate code. - Review Cloud Run staging deployment and application logs. - Prepare a detailed technical audit report. - Provide a realistic development roadmap and cost estimate. Phase 2 – Architecture and Backend Stabilization - Improve code structure and modular architecture. - Fix existing bugs and routing issues. - Review database consistency and permissions. - Improve error handling, logging and performance. Phase 3 – Business Module Completion - Verify and stabilize all existing business modules. - Ensure correct integration between Labour, Projects, DPR, Expenses and Accounts. - Preserve existing business rules and previously passed tests. Phase 4 – AI and Third-Party Integrations - Complete OpenAI and AI Agent integrations. - Stabilize WhatsApp Business API. - Complete Zoho Books integration. - Verify Document AI and invoice extraction workflows. Phase 5 – Security and Quality Assurance - Authentication and role-based access testing. - Firestore security audit. - Automated and regression testing. - API and integration testing. - Performance and reliability testing. Phase 6 – Final Deployment and Handover - Production-ready deployment. - Complete source code and technical documentation. - Database and deployment documentation. - Backup and recovery procedures. - Final testing and knowledge transfer. Mandatory Security and Ownership Requirements - All source code and intellectual property must belong to KCC. - All development must happen in our controlled staging environment. - Production access will not be provided during development. - No direct changes to production without written approval. - No sharing or copying confidential business data. - Developers must follow secure credential and access management practices. - All code must be committed to our private GitHub repository. Working Arrangement We prefer milestone-based development with clear deliverables and acceptance criteria. The first engagement will be a "paid technical audit". After reviewing the audit report, we will mutually agree on the remaining scope, timeline and budget. We are open to hiring an individual Senior Developer or a small experienced software development team. Required Experience Please apply only if you have strong practical experience in: - Node.js backend development. - Firebase and Firestore architecture. - OpenAI API and AI Agent development. - WhatsApp Business API integration. - Zoho Books or similar accounting API integration. - Google Cloud Run. - Production software debugging and system architecture. Please Include in Your Proposal 1. Your relevant experience with similar AI automation platforms. 2. Examples of Firebase, Node.js and OpenAI projects. 3. Your experience with WhatsApp API and accounting integrations. 4. Whether you are an individual developer or a software development team. 5. Your proposed approach for conducting the initial technical audit. 6. Estimated audit cost and completion time. 7. Your availability for long-term project completion. We are looking for a reliable technical partner who can take responsibility for the existing system and help us deliver a secure, stable and scalable business automation platform.