AWS Introduces Remote Build Cache in ECR to Accelerate Docker Image Builds

"Amazon Web Services has announced enhancements to its CodeBuild service, allowing teams to use Amazon ECR as a remote Docker layer cache, significantly reducing image build times in CI/CD pipelines. By leveraging ECR repositories to persist and reuse build layers across runs, organisations can skip rebuilding unchanged parts of containers and accelerate delivery. The blog outlines how Docker BuildKit support enables commands such as --cache-from and --cache-to pointing to ECR-based cache images,"

"allowing CodeBuild-initiated builds to pull cached layers from previous runs and push updated cache layers back to ECR. As a result, rebuilds can skip large parts of the Dockerfile when base layers remain unchanged, improving developer feedback loops and reducing build resource consumption. AWS emphasises that this approach addresses one of the major bottlenecks in container-based CI/CD: rebuild times driven by repeatedly constructing heavy dependency layers."

AWS CodeBuild can now use Amazon ECR as a remote Docker layer cache to persist and reuse build layers across CI/CD runs. Docker BuildKit commands --cache-from and --cache-to can point to ECR-based cache images so builds pull cached layers from previous runs and push updated layers back to ECR. Rebuilds can skip unchanged Dockerfile layers, lowering build durations, improving developer feedback loops, and reducing resource consumption. Remote caching complements local caches and provides a global cache across agents. Cache effectiveness depends on Dockerfile structure, multi-stage builds, and layer ordering. Setup requires an ECR repository, permissions, and BuildKit enabled.

Read at InfoQ