Reference¶
This page collects informative reference material - the package registry, discussion pointers, and a comparison with related work. The normative IANA / media-type considerations, security considerations, and the bibliography are in the Specification.
Registry¶
- OpenSemanticWorld Package Registry, deployed e. g. OpenSemanticWorld
Discussion¶
- In the context of YAML-LD: https://github.com/w3c/yaml-ld/issues/19
- The "LLM Wiki" pattern (persistent, LLM-maintained knowledge bases), and OO-LD's structured take on it: https://gist.github.com/karpathy/442a6bf555914893e9891c11519de94f
Related Work¶
Approaches to unifying structure and semantics¶
Keeping structure, semantics, shapes, docs and code in sync is a shared goal of many "polyglot" or "single-source" frameworks. They differ mainly on where the single source of truth lives and whether a build step is required. OO-LD's distinguishing choice is that the artefact is the source: one document is at the same time a valid JSON Schema and a referenceable JSON-LD remote context, with no separate modelling language and no compilation.
| Approach | Paradigm | Single source of truth | Build step | RDF / JSON-LD | Domain / adoption |
|---|---|---|---|---|---|
| OO-LD | Artefact is the source | JSON Schema + @context in one document |
none (optional delivery transforms) | yes (schema is a remote context; instances are JSON-LD) | general; scientific data in particular (OpenSemanticLab) |
| LinkML | Compile from metamodel | bespoke YAML metamodel | yes | generated context / RDF | biomedical; large, very active |
| SPDX 3.0 | Compile from model | constrained-Markdown model | yes | generated OWL + SHACL + JSON-LD context | SBOM / supply chain; ISO/OMG scale |
| TreeLDR | Compile from typed DSL | JSON RDF layout (records/fields) | yes | generated contexts / RDF | Verifiable Credentials / DIDs |
| yml2vocab | Vocabulary publishing | YAML term list | yes | RDFS vocab + JSON-LD context + HTML | W3C Verifiable Credentials vocabularies |
| Croissant | Fixed JSON-LD vocabulary | JSON-LD on schema.org/Dataset |
none | yes (JSON-LD) | ML datasets; NeurIPS, HuggingFace, Kaggle, Google |
| OCA | Overlays on a capture base | capture base + SAID-addressed overlays | bundle assembly | no (bridges via mapping overlay only) | Verifiable Credentials, DPP, privacy |
| Semantic Treehouse | Hub / registry | hosted OWL / SHACL / JSON Schema | n/a | yes | dataspaces vocabulary hub (TNO) |
| REST-API-LD | Annotate JSON Schema in place | JSON Schema / OpenAPI + x-jsonld-* |
none | yes (context via extension keywords) | eGovernment APIs (Italy); IETF I-D |
| WoT JSON Schema in RDF | Annotate JSON Schema in place | JSON Schema + instance-context | none | yes | W3C Web of Things; standards precedent |
Reading: the dominant paradigm is compile-from-a-source-language (LinkML, SPDX 3.0, TreeLDR, yml2vocab), which accepts a bespoke source plus a build step and must then keep generated artefacts in sync. Only REST-API-LD and WoT JSON-Schema-in-RDF share OO-LD's "annotate in place, no new language" property; REST-API-LD is the closest neighbour and is on a standards track. OCA is the opposite philosophy (decentralized overlays, not RDF-native), Semantic Treehouse is a hub rather than a language, and Croissant is a single-domain JSON-LD vocabulary with outsized adoption. The related layers OO-LD generates to - SHACL (logical) and OWL (conceptual) - are targets rather than competitors. Worked mappings from several of these formats to OO-LD are in Mappings.
Schema Overview¶
| Name | Description |
|---|---|
| JSON Schema | Base of this work. Does not include linked data concepts. |
| JSON-LD | Base of this work. Does not restrict the structure of a json file. |
| OWL | Focus on logical modelling. Only applicable to RDF. |
| SHACL | Only applicable to RDF. |
| Asset Administration Shell | Industry 4.0 related data schema for assets |
| Semantic Aspect Meta Model | SHACL subset / nested object-property schema written in turtle, e. g. used for the data models in Catena-X |
| SmartDataModels | JSON Schema defined data models used by FIWARE Foundation, TM Forum, OASC and IUDX |
| Common Data Model | Business related data models developed by Microsoft |
| Upper | Nested object-property schema written in turtle, similar to SAMM, developed by Netflix |
| LinkML | Custom schema language focussed on data modelling. Both importers and exporters to JSON Schema (and others) exists. Custom annotations for UI generation not (yet) supported (see #1618). |
| TreeLDR | Custom linked data schema language that can be converted to JSON Schema, JSON-LD context, RDF and Rust code |
| REST-API-LD | Annotated OpenAPI schemas with rendering support in Swagger-UI. Option to generate it from OO-LD. |
| dlite | Custom schema language focussed on scientific data |
| NOMAD | Custom schema language focussed on scientific data |
| Human Cell Atlas | Data schemas for the biology and medical domain |
| OTTR | Mixture of custom template and schema language. Limited toolset to convert from/to other formats. |
| TheWorldAvatar/ObjectGraphMapper | Class-RDF Mapping in Java via decorators |
| Cross-Domain Interoperability Framework (CDIF) | CDIF is a set of implementation recommendations, based on profiles of common, domain-neutral metadata standards which are aligned to work together to support core functions required by FAIR. |
| DDI-CDI | Cross domain meta data model between domain specific specifications and high - level specifications such as DCAT and Datacite |
| SPDX 3.0 | Model-driven SBOM / supply-chain standard. A single model generates an OWL ontology with SHACL shapes, a JSON-LD context and a JSON Schema; documents are validated both structurally (JSON Schema) and semantically (SHACL). Same polyglot thesis as OO-LD, but compiled from a bespoke model. |
| Croissant | MLCommons JSON-LD vocabulary for ML datasets, built on schema.org/Dataset. Heavy adoption (NeurIPS dataset tracks, HuggingFace, Kaggle, Google Dataset Search) and an MCP integration. Narrow domain, JSON-LD-native. |
| OCA (Overlays Capture Architecture) | Decentralized semantics: a minimal capture base plus stackable, content-addressed (SAID) overlays (labels, formats, units, mappings, ...). Own serialization, not RDF/JSON-LD/JSON Schema-native; the opposite philosophy to a single unified document. |
| yml2vocab | W3C tool that generates an RDFS vocabulary, a JSON-LD context and ReSpec/Bikeshed HTML from a simple YAML term list. Vocabulary-publishing, not a data-schema framework; used widely by the Verifiable Credentials community. |
| Semantic Treehouse | TNO vocabulary-hub platform for dataspaces. Hosts and collaboratively maintains vocabularies (OWL, SHACL and, more recently, JSON Schema) rather than defining a serialization; a registry counterpart to OO-LD schemas. |
| WoT JSON Schema in RDF | W3C note expressing JSON Schema as RDF and attaching a JSON-LD context to instances via jsonld:context. The closest standards precedent for annotating JSON Schema in place. |
Data Overview¶
| Name | Description |
|---|---|
| BIG-MAP | Battery-related linked data and ontologies (Battery Interface Genome - Materials Acceleration Platform) |