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Hi, I’m Hammad Ahmed, a Senior Full-Stack Engineer with 8+ years of experience building enterprise-scale web applications. I specialize in fintech and ecommerce, designing scalable microservices, implementing secure payment processing, and delivering high-performance apps used by millions of users. I thrive in cross-functional teams, collaborating with product, design, and security to define technical roadmaps and ship reliable software. I have hands-on experience with JavaScript (Node.js, React), Kotlin and Java, cloud infrastructure (AWS, GCP), and compliance-focused architectures including PCI DSS and real-time data processing.…Hi, I’m Hammad Ahmed, a Senior Full-Stack Engineer with 8+ years of experience building enterprise-scale web applications. I specialize in fintech and ecommerce, designing scalable microservices, implementing secure payment processing, and delivering high-performance apps used by millions of users. I thrive in cross-functional teams, collaborating with product, design, and security to define technical roadmaps and ship reliable software. I have hands-on experience with JavaScript (Node.js, React), Kotlin and Java, cloud infrastructure (AWS, GCP), and compliance-focused architectures including PCI DSS and real-time data processing.

Hammad Ahmed

Full Stack Developer, Front-End Developer, Back-End Developer, +4

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Hi, I’m Hammad Ahmed, a Senior Full-Stack Engineer with 8+ years of experience building enterprise-scale web applications. I specialize in fintech and ecommerce, designing scalable microservices, implementing secure payment processing, and delivering high-performance apps used by millions of users. I thrive in cross-functional teams, collaborating with product, design, and security to define technical roadmaps and ship reliable software. I have hands-on experience with JavaScript (Node.js, React), Kotlin and Java, cloud infrastructure (AWS, GCP), and compliance-focused architectures including PCI DSS and real-time data processing.…Hi, I’m Hammad Ahmed, a Senior Full-Stack Engineer with 8+ years of experience building enterprise-scale web applications. I specialize in fintech and ecommerce, designing scalable microservices, implementing secure payment processing, and delivering high-performance apps used by millions of users. I thrive in cross-functional teams, collaborating with product, design, and security to define technical roadmaps and ship reliable software. I have hands-on experience with JavaScript (Node.js, React), Kotlin and Java, cloud infrastructure (AWS, GCP), and compliance-focused architectures including PCI DSS and real-time data processing.

Available to hire

Hi, I’m Hammad Ahmed, a Senior Full-Stack Engineer with 8+ years of experience building enterprise-scale web applications. I specialize in fintech and ecommerce, designing scalable microservices, implementing secure payment processing, and delivering high-performance apps used by millions of users.

I thrive in cross-functional teams, collaborating with product, design, and security to define technical roadmaps and ship reliable software. I have hands-on experience with JavaScript (Node.js, React), Kotlin and Java, cloud infrastructure (AWS, GCP), and compliance-focused architectures including PCI DSS and real-time data processing.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

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Expert

Expert

Expert

Expert

Language

English

Fluent

Work Experience

Senior Full Stack Engineer at Walmart (Remote)

February 1, 2023 - Present

Contributed to the development of customer-facing e-commerce platforms serving 2M+ daily users using React.js, Node.js, and Express.js; implemented secure payment APIs with endpoint encryption; designed a real-time inventory management system handling 50,000+ SKUs with microservices and dashboards; built RESTful APIs for seamless integration between warehouses and customer applications; deployed microservices on AWS with Lambda and API Gateway; established CI/CD pipelines with automated testing and deployment; collaborated with a team of seven developers to ensure code quality and security; optimized API responsiveness and scalability across server and serverless architectures.

Full Stack Engineer at PayPal (Remote)

November 1, 2019 - January 31, 2023

Led backend overhaul of the merchant onboarding SAAS platform, migrating legacy PHP services to Node.js microservices with Express.js and MongoDB; developed real-time payment processing APIs handling 100K+ daily transactions using Socket.IO; implemented Redis-based session management and Memcached for API caching to improve performance; contributed to automated KYC verification workflows with third-party APIs; implemented secure OAuth2 and JWT for multi-tenant PCI DSS compliant endpoints; designed RESTful APIs for merchant dashboards and integrated with core payment rails; containerized applications with Docker and deployed on AWS ECS with CloudWatch monitoring; conducted comprehensive code reviews and mentored junior developers.

Senior Software Engineer at Wells Fargo (Remote)

May 1, 2017 - November 30, 2019

Contributed to Wells Fargo's online banking platform frontend using React.js, TypeScript, and Material-UI, serving 15M+ active customers with real-time account management capabilities; built secure authentication with MFA and session management using JWT and OAuth 2.0; designed scalable RESTful APIs for core banking operations including transfers, bill payments, and transaction history with SOX and PCI DSS alignment; developed a real-time fraud detection dashboard integrating ML models for security monitoring; implemented responsive mobile-first design with TailwindCSS and PWAs; deployed microservices on AWS (Lambda, ECS, DynamoDB) for high availability; integrated with third-party credit bureaus for loan processing.

Senior Full Stack Engineer at Walmart

February 1, 2023 - Present

Led design and implementation of customer-facing e-commerce platforms serving 2M+ daily users using React, Node.js, and Express; built real-time inventory management for 50k+ SKUs with Spring Boot microservices and MongoDB/PostgreSQL; created RESTful APIs linking warehouse systems to customer apps; deployed microservices on AWS with Lambda/API Gateway and CI/CD; improved API performance and reliability.

Full Stack Engineer at PayPal

November 1, 2019 - January 1, 2023

Led backend overhaul migrating legacy PHP services to Node.js microservices with Express.js and MongoDB; developed real-time payment processing APIs handling 100K+ daily transactions; built Redis/Memcached-based data pipelines for session management and API response caching; contributed to automated KYC workflows; implemented OAuth 2.0 and multi-tenant JWT-based authentication; containerized applications with Docker and deployed on AWS ECS; mentored three junior developers.

Senior Software Engineer at Wells Fargo

May 1, 2017 - November 1, 2019

Contributed to Wells Fargo's online banking frontend using React/TypeScript and Material-UI, serving 15M+ active customers with real-time account management; built secure authentication with MFA and session management; designed scalable REST APIs for core banking operations; developed real-time fraud detection dashboard and mobile-first UI enhancements with TailwindCSS and PWA features; deployed microservices on AWS for high availability with SOX and PCI DSS compliance; integrated with external credit bureaus for loan processing.