Cutting costs by moving off managed services is easy. Proving you didn’t just introduce new risk is the hard part. In this talk, we walk through how our team replaced a managed MongoDB deployment with a self-hosted stack while maintaining confidence in reliability. Rather than trusting infrastructure or best practices, we used proactive chaos testing to simulate the failures we knew would eventually happen in production. From node failures and disk loss to network partitions and replication edge cases, we tested how our system behaved under stress before customers ever experienced it. The results were not always what we expected. Some failures were handled seamlessly, while others revealed gaps that would have caused real incidents. This session is a practical story of what it actually takes to own reliability. You will learn how to use chaos engineering to validate migrations, uncover hidden risks in distributed systems, and make cost optimization decisions without compromising resilience.
Matt Schillerstrom is a product and technology leader specializing in DevOps, with a focus on Site Reliability Engineering and Chaos Engineering. He currently leads product management and product marketing at Harness, where he works on solutions that help teams deliver software more reliably and efficiently. With a background spanning engineering, product, and resiliency strategy at companies like Target and Gremlin, Matt brings a deep technical perspective to building and scaling modern software systems. He’s also an active community leader and mentor, organizing Chaos Engineering events and supporting others in the tech industry.
