Developer Portal of the Dutch Gov Launches Rest-Only, OpenAPI-First API Registry

The Developer Portal of the Dutch Government, Developer.overheid.nl’s API registry, will adopt a REST-only model and rely entirely on OpenAPI Specifications (OAS) to improve consistency, tooling support, and long-term maintainability, Product Owner Dimitri van Hees has announced.

A consolidation effort will merge all REST/JSON and REST/XML services, along with OData and OGC API geoservices, under a single REST category. Four less common protocols, GraphQL, CKAN, Atom and Socrata, will be deferred until wider adoption justifies separate handling.

Metadata fields such as API name, description, contact details, authentication schemes, server endpoints and documentation links will be sourced directly from submitted OAS documents. Mandatory design rules (ADR) will ensure each API declares info.title, info.contact and securitySchemes entries, while externalDocs and termsOfService links will enrich registry listings.

Ownership verification will shift from public-register lookups to API credentials issued by developer.overheid.nl. Linked-data identifiers from TOOI will map government agencies such as the Tax Authorities, preventing unauthorized entries and simplifying lifecycle management.

All registry operations, including adding, updating or retiring an API, will be exposed via a backend API. Daily synchronization with submitted OAS URLs and lifecycle status fields (active, deprecated, sunset, retired) driven by custom OAS extensions (x-deprecated, x-sunset) will keep listings current.

Planned enhancements include subscription alerts for API changes, Discourse forum integration, automatic conversion to OpenAPI 3.1, SDK generation, ADR compliance checks with how-to-fix guidance, API grouping via Arazzo and a modular, accessibility-compliant frontend component library.

The Municipality of Amsterdam has joined the registry pilot; further test participants are welcome. For full details and registration instructions, visit developer.overheid.nl.