Independent adapters

Adapters are peers around the source-neutral engine. No adapter receives special privileges.

OpenBIM

axioval-openbim provides a production IFC4 STEP path for exact direct properties: strict bytes become a SHA-256 fingerprinted EvidenceSession; IFC objects become source-qualified Axioval objects; and ifc-properties::exact_property backs the session’s property service with occurrence/type provenance and exact absence. The property resolver owns and declares the same source/revision/fingerprint/schema snapshot registered by the session; mismatched service composition is rejected. Parser diagnostics, unsupported schemas, malformed traversal, conflicts, and unsupported values fail closed.

Direct-property completeness does not imply relationship completeness. The IFC session deliberately registers no relationship-selection service yet. The adapter does not depend on Axiolid and does not own geometry policy.

Axiolid

axioval-axiolid supplies geometry evidence for any source capable of exposing Axiolid-compatible geometry handles. A proprietary CAD adapter can use it directly without importing OpenBIM or IFC.

ICDD

axioval-icdd opens an ICDD package, dispatches member payloads to registered source decoders, maps linksets, and assembles a project. ICDD serialization types do not cross into the engine IR.

Alternate geometry kernels

An OpenCascade or CGAL adapter may implement the same evidence traits in an external crate. Native/FFI code is never enabled by the default pure-Rust distribution.

Conformance

Every source adapter must prove source-qualified identity, deterministic enumeration, provenance and strict malformed-data behavior. Every geometry adapter must prove exactness reporting, backend-failure propagation, transform/unit handling and cache isolation.