regctl

About regctl

regctl is a CLI interface for Docker and OCI registries that provides efficient registry operations without requiring a container runtime or privileged access to the local host.

Key Features

• Registry Operations: Query tag listings, repository listings, and remotely inspect image contents
• Efficient Copying: Copy and retag images, only pulling layers when required, without changing image digests
• Multi-platform Support: Full support for multi-platform images and architecture-specific operations
• OCI Artifacts: Query, create, and copy OCI artifacts, storing arbitrary data in OCI registries
• Content Manipulation: Mutate existing images including annotations, labels, timestamps, and layer modifications
• No Runtime Required: Operates without container runtime or privileged access

Common Use Cases

• Image Management: Copy, retag, and inspect container images across registries
• Multi-platform Builds: Generate multi-platform manifests from separately built images
• Registry Migration: Efficiently migrate images between registries
• Content Inspection: Examine image contents, manifests, and metadata without pulling images
• OCI Artifact Storage: Use registries as generic artifact stores for any type of content
• Supply Chain Operations: Work with signatures, SBOMs, and other supply chain artifacts

Registry Compatibility

regctl works with any OCI-compliant registry, including:

• Docker Hub
• Amazon ECR
• Google Container Registry (GCR)
• Azure Container Registry (ACR)
• GitHub Container Registry (GHCR)
• Harbor
• Quay.io
• GitLab Container Registry
• And many others

Getting Started

The regctl CLI provides intuitive commands for common registry operations:

• regctl image - Image operations (copy, delete, inspect, manifest)
• regctl repo - Repository operations (list tags, delete)
• regctl tag - Tag operations (list, delete)
• regctl blob - Blob operations (get, put, delete)
• regctl artifact - OCI artifact operations
• regctl index - Multi-platform index operations

This Ghost hardened image provides a secure, minimal environment for running regctl operations in containerized workflows and CI/CD pipelines.