International Journal of Scientific Research and Engineering Development

This paper presents a scalable backend system for mental health monitoring and fitness recommendation, built using Node.js, Express.js, and MongoDB. The system integrates secure user authentication, mood tracking, journaling, exercise recommendations based on age, and an AI-powered mental-health chatbot using OpenRouter’s GPT model. A fallback emotional-response engine ensures reliability even when external AI services fail. The architecture, modules, database structure, analytics engine, performance metrics, and system evaluation are discussed in detail. The system demonstrates strong potential for real-world deployment as part of digital well-being platforms.