What is Strangler Fig Pattern?

Overview

The Strangler Fig Pattern is named after a type of tree that grows around its host, eventually replacing it. In software development, this pattern helps teams transition from legacy systems to modern architectures without a complete shutdown. By incrementally replacing parts of the old system with new code, developers can manage risk and ensure that the system remains operational during the change. This approach works by allowing new features or services to be built alongside the existing system. As new components are developed, they take over the responsibilities of the old ones. For example, if a company has an outdated customer management system, they might start by building a new system for handling new customer sign-ups while still using the old system for existing customers. Over time, as more features are migrated, the old system can be completely phased out. The Strangler Fig Pattern matters because it reduces the risk of failure during major system changes. Instead of a big bang approach where everything is swapped at once, this pattern allows for a smoother transition with less disruption. It also enables teams to learn and adapt as they go, making it easier to address issues that arise during the migration process.