The Federation Loom

An interactive, scored game that teaches federated ontologies: multiple ontologies will always exist — and that's healthy — but RDF links (SKOS/OWL) let them behave like one living, richer graph.

Play in two acts across four real US-focused vocabularies — CEDS and CTDL (the focus standards, underlined in gold on the graph) plus schema.org and EDUcore:

• Welcome + guided tour. A three-line welcome, then five popovers pinned to the real interface — what a cluster is, what a dot is, where you answer, what a right answer does. The tour layer never swallows clicks, so it hints rather than gates; Skip, Esc or Got it ends it, and the ? in the top bar replays it at any point.
• Prologue. Short: why multiple ontologies exist (and always will), plus the one rule the game grades on — concepts take SKOS, classes and properties take OWL/RDFS.
• Act I — The Weave. Judge which term in another vocabulary each term joins to; the loom weaves each connection as a visible RDF link on the graph.
• Act II — The Harvest. Run federated queries that only work across the links you wove.

Replaying the tour mid-game adds a sixth popover, How to pick well, anchored to the answer buttons — it restates the SKOS-versus-OWL rule where it is actually needed. That step is absent from the opening tour, which has no answers on screen yet.

Which link for which thing

The game is deliberate about this, because published crosswalks often aren't. SKOS mapping properties (skos:exactMatch, broadMatch, relatedMatch) are defined to hold between instances of skos:Concept — code-list and taxonomy entries such as a CIP program code or a SOC occupation. Ontology classes and properties take OWL/RDFS instead (owl:equivalentClass, rdfs:subClassOf, owl:equivalentProperty). So ceds:CredentialDefinition → ceterms:Credential is an owl:equivalentClass axiom, not a skos:exactMatch. (CEDS v14 has no class named Credential; Credential Definition is its counterpart, defined in CTDL's own words.)

The game is also explicit that alignment is not verification. A schema link makes a question askable across two systems; it says nothing about whether a particular learner's diploma is genuine. That takes an issuer-signed credential or an instance published in the registry by the issuer.

EDUcore on the graph

EDUcore, the education standards knowledge graph, is the fourth vocabulary. Its nodes in the game are real forged nodes from that graph: the SOC occupation 15-1252, the CIP program 11.0701 (one CLASSIFICATION_CROSSWALK edge apart, per the NCES crosswalk), CTDL-ASN's ceasn:Competency, and CEDS's Learning Resource class (C200228). EDUcore runs the same federation on a Neo4j property graph rather than an RDF triplestore: each standard's elements resolve to CEDS hub tuples by authored EXACT_MATCH or inferred CLOSE_MATCH edges, SUBCLASS_OF carries structure, and CLASSIFICATION_CROSSWALK carries CIP→SOC. Different storage, same principle: concepts align to concepts, structure aligns to structure. The game says this on the score screen.

The facts behind every join and query were checked against the live EDUcore graph via its MCP server (standards inventory, class definitions, crosswalk edges) — and that same MCP server is the point the score screen makes: an agent with access to the graph can walk the standards and propose these matches, including which kind each one has to be, instead of a human judging them one at a time. educore.org

The first play is a quick game (3 joins, 2 queries); the expanded loom (6 joins, 3 queries) unlocks from the score screen. Every visit and every replay deals a fresh random hand — which joins and queries appear, their order, and the order of the answer buttons — so a room full of players won't all see the same quiz. No login, no persistence — score lives only in the tab.

Run it

The whole site is one self-contained file. Either open index.html directly in a browser, or serve the folder:

python3 -m http.server 8080
# → http://localhost:8080

The only external dependency is Google Fonts; the game degrades gracefully to system fonts offline.

Deploy

Any static host works — there is no build toolchain, just the one HTML file.

Render. render.yaml in the repo root is a ready-to-use blueprint. In Render: New → Blueprint → pick this repo → Apply. It creates a static site that copies index.html into dist/ and publishes that, with PR previews on. To set it up by hand instead: New → Static Site, build command mkdir -p dist && cp index.html dist/, publish directory dist.

GitHub Pages. Push to GitHub, then Settings → Pages → deploy from the main branch root.

Grounded in

CEDS · CTDL · schema.org · EDUcore · SKOS · OWL. The CIP→SOC program-to-occupation crosswalk in the game is real, published by NCES, and carried in EDUcore as 8,324 CLASSIFICATION_CROSSWALK edges.