Karan Kumar Ratra
Walmart Global Tech· Sunnyvale, CA
Innovative E-Commerce Systems Architect and Technology Leader in Retail Technology

Driving Scalable Retail Innovation
Karan Kumar Ratra is a Senior Engineering Leader at Walmart Global Tech, where he leads globally distributed engineering teams building high-throughput, event-driven systems for the world’s largest retailer. With more than 16 years of experience across e-commerce, fintech, and telecom, he has architected and scaled platforms that handle 100M+ daily messages and power mission-critical retail operations.
Over the course of his career, Karan has delivered transformative technology initiatives:
- Walmart Fulfillment Management System (FMS): Architected and evolved Walmart’s core fulfillment platform, improving efficiency by 25% and reducing operational costs by 15%.
- PayPal Risk & Compliance Systems: Built compliance APIs and frameworks that prevented a potential $10M regulatory fine, earning him the prestigious PayPal Golden Envelope Award.
- Subex Credit Risk Management Platform: Designed scalable credit risk engines now deployed at Tier-1 and Tier-2 telecom operators worldwide.
Karan is also recognized as a thought leader and mentor:
- Awards: Walmart Impact Award 2024, multiple Walmart Excellence Awards, PayPal Golden Envelope Award, eBay Skunkworks Hackathon Winner, and more.
- Mentorship & Community: Top 1% Mentor on ADPList, Judge and Mentor at global hackathons including HackMIT, HackHarvard, and NASA Space Apps Challenge.
- Scholarship & Recognition: Senior IEEE Member, Distinguished Fellow of the Soft Computing Research Society (SCRS), Raptor Fellow, and Globee Award Winner (Technology Innovator, Engineering Excellence).
He is passionate about scalable distributed systems, event-driven architectures, and AI-driven innovation in retail technology. Beyond his technical expertise, Karan focuses on mentorship, cross-functional leadership, and fostering engineering excellence to deliver measurable business impact.
Selected Publications
- IJGISUnified Cloud Governance: Enhancing API Management and Digital Security with Knowledge GraphsIn International Journal of Global Information Systems (IJGIS), Aug 2024