Roles, employers, and the production case studies that came out of them. For independent work — open source and ventures — see Projects →.
Post-acquisition of Discover. Architecting cloud-native case management modernization on AWS — building toward real-time resolution that increases agent throughput and customer transparency. Also designed and built an ML fraud detection platform: model training pipeline on real transaction data, a real-time LLM-based decision layer, and graph-based fraud ring detection across accounts, devices, and merchants.
Led 8 cross-functional teams (40+ people) through core banking modernization — credit card posting, billing, statements — from data center to cloud-native AWS at 2,000+ TPS with 99.999% availability. Drove the Kafka Connect pipeline redesign that cut processing from 18 hours to 6 minutes. Rescued the ITP post-merger data migration that was stalled with no documentation and tribal knowledge in 1–2 people. Established ARB governance and InnerSource standards.
Sole architect for a unified ACH, RTP, and wire payments modernization strategy across multiple acquired banks — delivered the target-state architecture and a multi-phase integration roadmap, including the regulatory compliance path, independently.
Worked directly with the CEO and VP of Technology — no intermediary layer — to define cloud-native AWS architecture for an AI-powered patient IVR platform and design EHR interoperability via Iguana HL7 interfaces. Translated architecture into business value language, not engineering jargon.
Architected and modernized payment platforms — in-store, web, mobile, third-party — for Walmart, Saks, Kohl's, and Menards. 900M+ record (~1.5 TB) cloud migration, 40% API latency improvement, deployment cycles from 14 hours to 1 hour via CI/CD. Built the DRM document management system from scratch to replace an undocumented black box — case closure efficiency up 78%, $20M in savings. Led Small Business Credit Card cloud-native transformation — 40% increase in applications, $8M annual savings, 200K+ developer hours saved. Mentored 50+ developers.
Legacy modernization for CGI, Affordable Care Health, U.S. Department of the Interior, and GE Healthcare — across healthcare, government, and IoT, before cloud-native was the default answer.
Architecture reviews, migration strategy, or standing advisory hours for teams navigating exactly the kind of problems on this page — not a full-time hire, not a one-off call, a standing relationship with someone who's actually done this before.
Get in touch →A batch pipeline bottlenecked at 10–15 TPS through a single internal API — not a tuning problem, a design ceiling. Rebuilt using Kafka Connect source and sink connectors, bypassing the API entirely. Exactly-once delivery, zero duplicate events, $300K annual infrastructure savings, 21K developer hours eliminated. In production.
Inherited a stalled, post-merger migration program — no documentation, open decisions everywhere, institutional knowledge in 1–2 people who were leaving. Built the process from scratch: closed every open mapping decision, documented what didn't exist, drove it to green.
The existing system was a black box — no documentation, no original engineers, no one who knew how it worked. Built a replacement from scratch, mapped from what the system actually did in production. Case closure efficiency up 78%, $20M in savings.
Architected in-store, web, mobile, and third-party payment platforms for Walmart, Saks, Kohl's, and Menards. 900M+ records (~1.5 TB) migrated to cloud, 40% API latency improvement, deployment cycles cut from 14 hours to 1 hour.
Arun consistently demonstrated a deep understanding of our organization's complex systems and effectively translated business requirements into scalable technical solutions. His strategic thinking and innovative approach were instrumental in driving our digital transformation initiatives forward.
Arun consistently demonstrates an exceptional level of expertise and professionalism in his work. His architectural designs are not only innovative but also meticulously crafted, showcasing a deep understanding of both aesthetic and functional aspects.
Arun was one of my favorite programmers to work with. He is a great problem solver, always ready to push his skills to the next level. Even though it's been a couple of years, I'd work with him again in a heartbeat.
What stands out about Arun is his command over a broad technical stack paired with a rare ability to distill complex projects into clear, actionable takeaways. He has a gift for guiding engineering teams through technical presentations, always taking the time to explain the reasoning behind his recommendations and walk through tradeoffs.
He was methodical, taking the time to actually understand how the system worked before proposing changes, rather than jumping straight to a fix. When things got stressful or the timeline got tight, he stayed calm and helped focus the team — an initiative that had been stalled for weeks was resolved cleanly, in time to meet compliance deadlines.