New Features¶
Fusion Metadata Registry 12 introduces a set of changes aimed at both day-to-day registry operations and longer-term platform scalability. This release strengthens auditability and governance through metadata time travel and semantic versioning, broadens enterprise integration with modern authentication options, and improves performance for registries managing larger and more complex metadata estates.
For technical readers, FMR 12 adds support for new SDMX capabilities, more flexible security integration, and an architecture designed for higher metadata volumes. For business and programme stakeholders, the release improves traceability, reduces operational risk, and supports growth without a corresponding increase in memory demand.
12.5.0 Performance and Scaling¶
FMR 12.5.0 builds on the performance improvements for large structures introduced in the 12.0.0 release. A re-engineering of the cross-reference resolvers has dramatically improved memory efficiency and performance when processing structural metadata containing millions of cross-references.
Local testing on an Apple M3 Mac with an 8 GB Java heap demonstrates the scale of these improvements. A large Representation Map referencing 6 million Codes was persisted in 67 seconds. Six Codelists, each containing 1 million Codes, were persisted in 70 seconds, with a query for an individual Codelist completing in just over 1 second.
12.0.0 Metadata time travel¶
FMR 12 records the history of changes made to every artefact, making it possible to query structures exactly as they existed at a specific point in time. This capability is exposed through the SDMX structure REST API v2.2.0 asOf parameter.
Get the latest versions of all codelists as stubs as they were at 16:00 UTC on 12 April 2026:
https://example.registry.com/sdmx/v2/structure/codelist/*/*/~/?format=sdmx-3.0&detail=allstubs&asOf=2026-04-12T16:00:00Z
Time travel also works with reference metadata reports.
Get the metadata report ABC:REPORT1(1.0) as it was at 09:00 UTC on 15 July 2026:
Typical use cases include:
- validating datasets against the structural metadata that was in force when the data were created
- supporting audit and compliance requirements
- debugging change histories and identifying when a specific update was introduced
12.0.0 Semantic versioning¶
FMR 12 implements the SDMX 3.1 semantic versioning specification together with the versioning rules defined in the TWG/SWG semantic versioning guidelines. This gives organisations a clearer and more predictable way to manage change, especially where metadata structures are shared across teams or external consumers.
Maintain semantic and non-semantically versioned structures in the same registry
Immutable artefacts: structures with semantic version numbers can only be changed by creating a new version
Wildcard cross referencing
Automatic detection of the scope of changes and application of versioning rules; for example, deleting codes from a codelist is identified as a breaking change and forces a new major version
Handling of draft structures identified by the _draft suffix
Handling of zero-versioned structures, which are considered draft by default
12.0.0 OIDC authentication¶
The authentication subsystem has been reengineered to support multiple authentication methods, making FMR 12 easier to align with enterprise security standards. The release adds OpenID Connect (OIDC) support for both interactive users and machine-to-machine integration.
- Supports OIDC authentication for both interactive users and machine-to-machine clients
- Supports the OAuth 2.0 authorisation code flow for interactive access, with or without PKCE
- Supports the OAuth 2.0 client credentials flow for machine-to-machine access
FMR 12 now supports five authentication approaches:
- Internal superuser account: FMR's built-in authentication service provides a single
rootsuperuser account created during installation - OpenID Connect (OIDC): for environments where identity is managed by an OAuth 2.0 identity provider (IdP)
- Directory services: for environments using Microsoft Active Directory (AD) or a generic LDAP directory service
- Custom security services: for authentication mechanisms such as CAS or SPNEGO supported by Tomcat authentication valves
- X.509 client certificates: for interactive users or machines authenticating with a client certificate
FMR 12 integrates with major OAuth/OIDC identity providers including Microsoft Entra ID and Keycloak.
12.0.0 Lower memory usage and support for 'big metadata' use cases¶
FMR 12 introduces an updated content storage approach to support significantly larger metadata estates while reducing platform memory demand. FMR 11's pure in-memory model has been replaced by a more sophisticated strategy that uses the database as the primary store, reducing the dependency between deployment memory and registry size.
- Platform memory demand no longer scales linearly with registry content
- Designed to support "big metadata" scenarios with both large structures and high volumes of artefacts
- Provides a stronger foundation for semantic versioning, where immutable structures require a new version for each change
Testing indicates that platform memory of 16GB should be sufficient for many production use cases.
Like Redis, FMR 11 was designed as a pure in-memory model to maximise retrieval performance for metadata driven processes. It also assumed that the volume of metadata would remain relatively compact. That assumption no longer holds true. Moreover, metadata caches now solve the retrieval performance problem. Thus FMR 12 sacrifices a bit of retrieval performance in return for a lower memory footprint and importantly avoids the need to scale platform memory in proportion to the content volume.