VCKit Adapter

VCKit is an open-source verifiable credential toolkit that provides credential signing, verification, DID management, and cryptographic key management. It is the default verifiable credential service bundled with the Reference Implementation.

About VCKit

VCKit is a standalone service that exposes a set of REST APIs for working with W3C Verifiable Credentials and Decentralised Identifiers. It requires its own PostgreSQL database for storing keys, DIDs, and credential metadata.

• Repository: github.com/uncefact/project-vckit
• Docker image: ghcr.io/uncefact/project-vckit When using the Docker Compose configuration from the Reference Implementation repository, VCKit and its database are provisioned automatically. When running the Reference Implementation Docker image standalone, VCKit must be provisioned separately — refer to the VCKit repository for setup instructions.

Supported Version

The supported version of VCKit is sha-325b7e3.

Multi-Tenancy

VCKit is a single-tenant system. The Reference Implementation adds a multi-tenancy isolation layer on top: each tenant's DIDs are registered in the Reference Implementation database, and the API enforces that tenants can only sign credentials using DIDs belonging to their own tenant.

Environment Variables

The following environment variables configure the connection between the Reference Implementation and a VCKit instance:

Variable	Description	Required	Default
SYSTEM_VC_BASE_URL	Base URL of the VCKit instance	Yes	http://localhost:3332
SYSTEM_VC_API_KEY	Authentication token for the VCKit API	Yes	test123
SYSTEM_VC_ADAPTER_TYPE	Must be set to VCKIT	Yes	VCKIT
SYSTEM_VC_SERVICE_NAME	Display name for this service instance	No	System Default VC
SYSTEM_VC_SERVICE_DESCRIPTION	Description for this service instance	No	—
SYSTEM_VC_API_VERSION	API version	No	1.0.0

These variables are used during startup to seed the default verifiable credential service instance into the system tenant.

API Configuration Schema

When creating or updating a VCKit service instance via the Services API, the config object must conform to the following schema:

Field	Type	Required	Default	Description
baseUrl	string (URL)	Yes	—	Base URL of the VCKit instance (e.g., http://vckit-api:3332)
apiKey	string	Yes	—	Authentication token for the VCKit API. Sensitive — masked in API responses.
apiVersion	string	Yes	1.0.0	API version to use when communicating with VCKit

Example:

{
  "baseUrl": "https://vckit.example.com",
  "apiKey": "your-api-key",
  "apiVersion": "1.0.0"
}