AWS has announced CDK Mixins, a new feature in the AWS Cloud Development Kit that enables composable, reusable infrastructure abstractions. Unlike traditional L1/L2/L3 constructs that bundle all features together, Mixins let developers apply modular capabilities to any construct type after creation — whether L1, L2, or custom — without being locked into specific implementations. Key capabilities include universal compatibility across construct types, cross-service abstractions (e.g., vended log delivery across 47 AWS resources), type safety, and three behavior control modes (graceful, requireAll, requireAny). Built-in mixins cover S3 public access blocks, ECS cluster settings, and log delivery. Custom mixins are created by extending cdk.Mixin and implementing the IMixin interface. Core functionality ships with aws-cdk-lib, with service-specific mixins accessed via standard service imports.
