Strangler Fig on IBM Kubernetes: Modernizing a Monolith Without Breaking Production

The article discusses modernizing monolithic applications using the Strangler Fig pattern to avoid risky rewrites. This approach involves incrementally extracting parts of the monolith into separate services. It provides a step-by-step guide using IBM Cloud Kubernetes Service (IKS) for containerizing, deploying, and routing traffic. The process begins with containerizing the existing monolith and deploying it to Kubernetes behind an Ingress. Next, new services are built and deployed, with ingress rules directing traffic based on paths to either the monolith or the new service. The guide then emphasizes a safe rollback strategy using easily adjustable ingress configurations or deployment rollbacks. Finally, the article encourages repeating this pattern for other bounded domains to gradually shrink the monolith and reduce risk. This methodology allows for production-safe modernization, avoiding downtime or major overhauls.