Context
'Built on open standards' is easily said. Here is the concrete list, by architectural layer, with what each standard does in Weaver. Every layer is independently replaceable, if you change RDF stores, the data moves; if you change query engines, the queries still work; if you change BIM authoring tools, the IFC interface is unchanged.
Five layers, all open, all replaceable.
Explanation
The platform stacks several layers of open standards:
Data foundation, the W3C semantic-web stack
RDF (W3C, 1999) is the data model. SPARQL (W3C, 2008) is the query language. SHACL (W3C, 2017) is the validation language. OWL (W3C, 2004) is the ontology language. Twenty years stable, vendor-neutral, fully specified.
Domain metamodel, ISO 15926-11
ISO 15926-11 is the reference data library for asset information across the process and energy industries. It defines core classes (Physical Object, Functional Object, Activity, Property) and the relationships between them. Weaver's standard model ships with ISO 15926-11 pre-configured.
Information management, ISO 19650 (and NEN 2660 in NL)
ISO 19650 governs the container lifecycle, suitability states and naming conventions for BIM information. NEN 2660 is the Dutch information modelling standard, relevant for Netherlands-based programmes.
BIM interoperability, the buildingSMART suite
IFC (ISO 16739) for 3D model exchange. BCF for issue management. openCDE for CDE-to-CDE communication. Weaver implements the buildingSMART API suite end-to-end.
APIs, REST, GraphQL, OData
Standard wire protocols. Language-neutral. Every Weaver capability is accessible programmatically.
The point of stacking open standards by layer is that no single standard is a single point of failure. If one of them is superseded by a successor (as standards eventually are), the migration happens at one layer, not throughout the system.