Gunnar Grosch, a Senior Developer Advocate at AWS, discusses his journey from being an AWS user to becoming an AWS Serverless Hero and his current role in promoting serverless reliability through Chaos Engineering. He emphasizes the importance of testing serverless systems for resilience, despite their inherent reliability, by using techniques like Chaos Engineering to examine how different serverless components interact under stress. Grosch highlights the challenges of maintaining documentation and mental models in dynamic serverless environments and advocates for integrating observability and tracing early in the development process. He also introduces AWS Resilience Hub, a new service that leverages the AWS Well-Architected Framework to help users assess and improve their system's resilience, offering recommendations for enhancing architecture and running chaos experiments through AWS Fault Injection Simulator. Grosch encourages hands-on experience with these tools to promote the adoption of Chaos Engineering practices.