Contract Registry

What Is a Contract?

A contract is any architectural construct that crosses project boundaries - a projection that another team consumes, a schema that multiple services share, or an API that external systems call. When an artefact containing one of these constructs is imported into the hub, the contract registry automatically creates or updates a contract entry.

Contract Data Model

Version Coexistence

Multiple versions of a contract can be active simultaneously. When a producer publishes a new version, consumers do not need to migrate immediately. The registry tracks which consumers are on which version, and the mesh view shows version drift with health indicators (green for current, amber for behind). This supports gradual, phased migration rather than big-bang upgrades.

Approval Workflow

Every contract version passes through an approval workflow. New versions arrive with a pending status. The estate architect reviews the changes - comparing content snapshots between versions, checking compatibility classification, and assessing consumer impact. Versions can be approved for distribution or rejected with a reason. The approval decision, timestamp, and approver name are recorded as an audit trail.

Content Snapshots and Diffing

Every version stores a full content snapshot - the complete JSON content of the contract at that point in time. This makes it possible to diff any two versions without needing access to the original workspace. The contract detail view shows a version timeline with the ability to compare adjacent versions and see exactly what changed.

Contract Types