How Spring Cloud Gateway Orchestrated Our App Modernization

App modernization is a tricky endeavor, especially when your apps consist of high-volume, customer-facing services for a brand that prides itself on user experience. It is crucial to introduce modernized components incrementally and maintain backward compatibility for existing consumers; in other words, strangling the monolith. At AARP, we utilized Spring Cloud Gateway integrated with VMware Tanzu Application Service early in our modernization efforts, and used it for traffic shaping between monolith and new microservices, A/B testing, API manipulation, and blue-green deployments. Throughout this talk, we will review the use cases we faced in our modernization and how Spring Cloud Gateway enabled AARP to replatform our services safely and with precision.