Raphael Pionke, a DevOps Engineer at T-Systems MMS, outlines a modernized approach to application performance and resiliency testing, focusing on white-box testing using JMeter and Dynatrace. This methodology aims to address complex cloud architectures by providing visibility from the end-user to code-level, thereby facilitating proactive problem resolution and scalability optimization. The white-box testing approach integrates JMeter with Dynatrace to enhance automation and transparency, using tools like the W3C Trace Context for detailed traceability and Dynatrace's AI for root cause analysis. Automating the test infrastructure setup with Terraform and Ansible, along with using a self-developed test management tool, ensures efficient test result tracking and analysis. Future enhancements include collaboration with Dynatrace on the open-source project Keptn, to improve automation and integration across various DevOps tools and processes.