Harbor is an open source trusted cloud native registry project written in Go that extends Docker Distribution with enterprise-grade security, identity management, and governance capabilities. Hosted by the Cloud Native Computing Foundation, Harbor serves as a registry for cloud native environments supporting both container images and Helm charts, making it suitable for container runtimes and orchestration platforms like Kubernetes.
The project implements role-based access control where users access different repositories through projects with granular permission management for images and Helm charts. Harbor includes policy-based replication functionality that synchronizes images and charts between multiple registry instances using filters for repository, tag, and label, with automatic retry mechanisms for failed replications. This feature supports load balancing, high availability, and multi-datacenter deployments in hybrid and multi-cloud scenarios.
Security features are central to Harbor's design. The system performs regular vulnerability scanning of images with policy checks to prevent vulnerable images from being deployed. Harbor supports image signing using Docker Content Trust through Notary, guaranteeing authenticity and provenance, and can enforce policies preventing unsigned images from deployment. The platform integrates with enterprise authentication systems through LDAP and Active Directory support, allowing organizations to import LDAP groups and assign project permissions. OpenID Connect support enables single sign-on capabilities through external authorization servers and identity providers.
Harbor provides comprehensive operational capabilities including image deletion and garbage collection for freeing up space from dangling manifests and unreferenced blobs, a graphical user portal for browsing and managing repositories, and complete activity auditing that tracks all repository operations. The system offers RESTful APIs with an embedded Swagger UI for administrative operations and programmatic integration with external systems.
Deployment flexibility is a key strength, with Harbor supporting Docker Compose deployment, Helm Chart installation for Kubernetes environments, and a Harbor Operator for additional deployment options. The project maintains OCI Distribution Conformance compliance and provides compatibility lists for replication adapters, OIDC adapters, and scanner adapters.
Harbor shares contributors with major projects including Microsoft VSCode, Microsoft TypeScript, and Rust-lang/Rust, demonstrating its significance in the broader open source ecosystem.
