Ihsaan Khan

Full Stack Developer & AI Engineer

Fiverr • Freiberufler

Jun 2020 - Present • 5 yrs 11 mos

Delivered 130+ successful projects for startups, SMBs, and global enterprise clients across SaaS development, custom API engineering, AI integration, and business automation. Built end-to-end multi-tenant SaaS platforms with subscription billing, role-based access control, admin dashboards, analytics panels, and complex business logic using Java, Spring Boot, Angular, React, Next.js, Node.js, and Lovable. Designed and optimized databases with PostgreSQL, MongoDB, Supabase, Firebase, and Redis for high-traffic, data-intensive applications. Developed high-performance RESTful APIs, GraphQL endpoints, and microservices architecture for scalable backend systems. Integrated third-party APIs including payment gateways (Stripe, Paddle, PayPal, Shopify), CRM tools, email services, and cloud storage with fault-tolerant error handling and comprehensive documentation. Specialized in AI-powered application development - integrated OpenAI GPT-4, LangChain, RAG pipelines, ElevenLabs voice AI, and Stable Diffusion into production-grade web applications. Built custom AI chatbots, intelligent recommendation engines, NLP-powered search features, AI voice assistants, and automated content generation systems. Created end-to-end automation workflows using n8n, Make.com, and Zapier for lead generation, email marketing campaigns, B2B outreach systems, CRM automation, data scraping pipelines, and business process optimization - saving clients hundreds of manual hours monthly. Handled full cloud deployment and DevOps using AWS, Docker, and CI/CD pipelines. Performed PageSpeed optimization, Core Web Vitals tuning, server response time improvements, and SEO performance enhancements to ensure fast, production-ready applications. Maintained a consistent 5-star rating with on-time delivery, fast communication, clean documented code, and long-term client relationships. Projects range from rapid MVPs to enterprise-scale platform launches across industries, including fintech, healthtech, e-commerce.

Senior Software Engineer | Full Stack

Software Engineering Daily • Vollzeit

Dec 2018 - Dec 2024 • 6 yrs

I worked as a Full Stack Software Engineer at JFreaks Software Solutions, building enterprise-grade SaaS API platforms from concept to production deployment - architecting systems that today serve millions of API requests daily. Key Achievements: • Architected and developed CurrencyFreaks.com - a complete SaaS platform delivering real-time and historical exchange rate data via REST API using Java, Spring Boot, and Angular • Built and maintained IPgeolocation.io - an enterprise API platform for IP-based geolocation, timezone intelligence, and threat detection serving millions of requests • Built and maintained whoisfreaks.com - an enterprise API and Database platform to gain real-time DNS, domain, and IP intelligence to strengthen security, protect your brand, and drive smarter decisions with our advanced data platform. • Implemented multi-tenant architecture supporting thousands of concurrent users across tiered API subscription plans with automated billing via Stripe, Paddle, Fast Spring. • Established production monitoring, automated alerting, and incident response workflows for mission-critical API services using AWS CloudWatch • Led junior developers and conducted regular code reviews, maintaining high code quality standards • Designed and implemented database optimization strategies with PostgreSQL for high-performance API data serving Tech Stack: Java, Spring Boot, Spring MVC, Spring Security, Angular, TypeScript, PostgreSQL, MySQL, AWS (EC2, S3, RDS), Docker, REST APIs, Redis, Stripe