At Chaos Conf 2019, Datadog Technical Evangelist Jason Yee discussed the importance of monitoring in software development, emphasizing that developers should incorporate monitoring into their code to ensure system resilience. Yee highlighted different monitoring frameworks like RED, USE, and Google's four golden signals, and underscored the need for developers to emit metrics and set alerts directly within their code. He advocated for a proactive approach, integrating monitoring and chaos testing early in the development cycle to validate system functionality and resilience. This approach, termed "resilience driven development," encourages developers to build resilient applications by testing them against simulated failures, thereby ensuring they meet customer needs effectively. By shifting monitoring responsibilities to developers and using tools like Datadog and Gremlin, teams can automate and streamline the process, making resilience a first-class aspect of software development.