Blue-green deployment vs progressive delivery: Choosing a deployment strategy

Blue-green deployment and progressive delivery are two distinct software deployment strategies that offer different methods for managing application updates. Blue-green deployment involves maintaining two identical production environments, where one is live while the other is idle, allowing teams to switch traffic seamlessly between them and provide instant rollback capabilities, though it requires double the infrastructure resources. In contrast, progressive delivery gradually introduces new features or versions to users, using techniques like canary releases and feature flags to minimize risk exposure and validate changes with real users incrementally, without needing duplicate infrastructure. While blue-green deployment is simpler but resource-intensive, offering zero-downtime and immediate rollback, progressive delivery emphasizes incremental exposure and data-driven adjustments, making it more complex but cost-effective. Both strategies have their advantages and are chosen based on deployment speed requirements, infrastructure budget, risk management needs, and the complexity of the application.