What is artifact storage in CI/CD and why is it important?

Artifact storage refers to storing the outputs of a CI build — compiled binaries, JAR files, ZIP archives, Docker images — in a durable repository so they can be deployed reliably later. The key principle is build once, deploy many: compile the artifact once in CI, store it, and promote that exact same artifact through staging and production. This eliminates the risk of a re-build producing slightly different output due to dependency changes or environment differences. For Docker images, a container registry (Docker Hub, AWS ECR, Google GCR, GitHub Container Registry) stores and versions images by git SHA or semantic version tag. For binary artifacts, tools like Nexus, Artifactory, or cloud-native solutions (AWS S3, GitHub Packages) store versioned packages.