Skip to content


Switch branches/tags

Name already in use

A tag already exists with the provided branch name. Many Git commands accept both tag and branch names, so creating this branch may cause unexpected behavior. Are you sure you want to create this branch?

Latest commit


Git stats


Failed to load latest commit information.
Latest commit message
Commit time


Go Workflow Status Docker Workflow Status Dependency Workflow Status Vulnerability Workflow Status

Go Reference License OpenSSF Scorecard OpenSSF Best Practices

Client interface for the registry API. This includes regctl for a command line interface to manage registries.

regctl demo

regclient Features

  • Provides a client interface to interacting with registries.
  • Images may be inspected without pulling the layers, allowing quick access to the image manifest and configuration.
  • Tags may be listed for a repository.
  • Repositories may be listed from a registry (if supported).
  • Copying an image only pulls layers when needed, allowing images to be quickly retagged or promoted across repositories.
  • Multi-platform images are supported, allowing all platforms to be copied between registries.
  • Digest tags used by projects like sigstore/cosign are supported, allowing signature, attestation, and SBOM metadata to be copied with the image.
  • OCI subject/referrers is supported for the standardized replacement of the "digest tags".
  • Digests may be queried for a tag without pulling the manifest.
  • Rate limits may be queried from the registry without pulling an image (useful for Docker Hub).
  • Images may be imported and exported to both OCI and Docker formatted tar files.
  • OCI Layout is supported for copying images to and from a local directory.
  • Delete APIs have been provided for tags, manifests, and blobs (the tag deletion will only delete a single tag even if multiple tags point to the same digest).
  • Registry logins are imported from docker when available
  • Self signed, insecure, and http-only registries are all supported.
  • Requests will retry and fall back to chunked uploads when network issues are encountered.

regctl Features

regctl is a CLI interface to the regclient library. In addition to the features listed for regclient, regctl adds the following abilities:

  • Formatting output with templates.
  • Push and pull arbitrary artifacts.

regsync features

regsync is an image mirroring tool. It will copy images between two locations with the following additional features:

  • Uses a yaml configuration.
  • The regclient copy is used to only pull needed layers, supporting multi-platform, and additional metadata.
  • Can use user's docker configuration for registry credentials.
  • Ability to run on a cron schedule, one time synchronization, or only check for stale images.
  • Ability to backup previous target image before overwriting.
  • Ability to postpone mirror step when rate limit is below a threshold.
  • Ability to mirror multiple images concurrently.

regbot features

regbot is a scripting tool on top of the regclient API with the following features:

  • Runs user provided scripts based on a yaml configuration.
  • Scripts are written in Lua and executed directly in Go.
  • Can run on a cron schedule or a one time execution.
  • Dry-run option can be used for testing.
  • Built-in functions include:
    • Repository list
    • Tag list
    • Image manifest (either head or get, and optional resolving multi-platform reference)
    • Image config (this includes the creation time, labels, and other details shown in a docker image inspect)
    • Image rate limit and a wait function to delay the script when rate limit remaining is below a threshold
    • Image copy
    • Manifest delete
    • Tag delete

Development Status

This project is in active development. Various Go APIs may change, but efforts will be made to provide aliases and stubs for any removed API.


See the installation options.


See the project documentation.