Md Zobayer Hossain M.

I help businesses to build, improve, and scale reliable backend systems, APIs, and AI-powered features that work smoothly in production. My focus is simple: build backend solutions that are stable, secure, maintainable, and ready for real users. Whether you need a new backend, API development, third-party integration, performance improvement, or AI-powered automation, I can help turn your requirements into a working production-ready system. Backend Development I build and improve backend systems for web apps, SaaS platforms, admin panels, automation tools, and business applications. I can help with: - Backend architecture and development - REST API design and implementation - Database-driven backend systems - Authentication and authorization - Performance optimization - Debugging and fixing backend issues - Refactoring and improving existing systems - Production deployment support AI & LLM Integration I help businesses add practical AI features into their products and workflows. I can help with: - OpenAI, Claude, Gemini API integration - AI chatbot backend development - LLM-powered automation workflows - AI content generation features - AI data processing and summarization - Prompt-based backend workflows - Connecting AI features with existing products - Building secure backend logic around AI usage API Integrations I work with third-party APIs and integration-heavy backend systems. I can help with: - Payment gateway integration - CRM, SaaS, and business tool integrations - Webhook handling - API troubleshooting and debugging - External service connection - Data synchronization between systems - Custom integration workflows - Fixing broken or unstable integrations Tech Stack - Backend: Node.js, NestJS, Express.js, Python, FastAPI - Databases: PostgreSQL, MongoDB, MySQL, Redis - APIs: REST APIs, Webhooks, Third-party APIs - AI/LLM: OpenAI API, AI automation, chatbot backend, LLM workflows - Cloud & Deployment: AWS, VPS, Docker, Nginx, Linux servers - Other: Authentication, security best practices, performance optimization