Registry - CI/CD Glossary Definition

A registry is a server that stores and distributes container images (and other OCI artifacts) addressed by repository name, tag, and digest. Docker Hub, GitHub Container Registry (ghcr.io), Amazon ECR, and Google Artifact Registry are common examples.

How CI uses it

A pipeline authenticates to a registry, pushes the image it built, and later pulls it for testing or deployment. Pull/push happen over the OCI distribution API, and images are deduplicated by layer digest so shared layers are not re-uploaded.

Login example

.github/workflows/ci.yml

echo "$TOKEN" | docker login ghcr.io -u "$USER" --password-stdin
docker push ghcr.io/org/app:1.2.3

Related guides

OCI Image - CI/CD Glossary DefinitionOCI Image: An OCI image is a container image that follows the Open Container Initiative image specification:… Pull Rate Limit - CI/CD Glossary DefinitionPull Rate Limit: A pull rate limit is a cap a registry places on how many image pulls a client may perform in… Image Tag Immutability - CI/CD Glossary DefinitionImage Tag Immutability: Image tag immutability is a registry setting that prevents an existing tag from being…