PurRDF

Why PurRDF?

RDF tooling fragments across languages and across standard generations. Every ecosystem has its own parser, serializer, store model, and edge-case behavior, while RDF 1.2 adds triple terms, reifiers, and base-direction literals that many incumbent libraries do not carry yet.

PurRDF keeps those semantics in one core. The Rust implementation is the behavioral center; bindings and package surfaces expose that same engine rather than reimplementing the graph model per language.

What's inside

Install

Interfaces

The public facade is the purrdf umbrella crate: it re-exports the RDF 1.2 surface at its root and carries every other published crate under a stable module, so a Rust consumer never reaches into a sub-crate. Twenty-one crates publish in lockstep, splitting the kernel, codecs, GTS, SPARQL algebra, evaluation and results, composite datatypes, SHACL, ShEx, entailment, Datalog, full-text, GeoSPARQL, columnar export, slices, IRIs, XSD values, events, and the WebAssembly engine; purrdf-validate is the shared host boundary the bindings call. Four workspace members are deliberately never published: the C ABI crate, the conformance harness, the CLI, and the Python extension crate.

The Python package ships an rdflib compatibility layer and a GTS fold view. The JavaScript package exposes an RDF/JS-shaped DataFactory, Dataset, and stream surface over the same engine, plus SHACL validation to SARIF, entailment materialization, governed SPARQL with explain receipts, and graph identity through canonicalize() and isomorphic().

The minimum supported Rust version is 1.96 on the stable channel.

cargo add purrdf
pip install purrdf
npm i @blackcatinformatics/purrdf

Conformance

Every engine is gated by its official test suite, vendored and frozen in the source repository. The full scoreboard is in CONFORMANCE.md.

Development gates are exposed in the upstream repository as make metadata, make check, and make bench.

Place in the GMEOW family

PurRDF is the library layer under GMEOW, Blackcat Informatics' reasoning-centric ontology and grounded-memory publication stack. It also hosts the Rust GTS engine; GTS remains the graph-transport format and project surface.

PurRDF was extracted from the GMEOW ontology engine, and the consumer relationship now runs the other way: GMEOW has deleted its own RDF kernel and consumes PurRDF instead.

Documentation

• The PurRDF Book - the user guide: getting started in each language, concepts, and every engine. Published in English.
• RDF 1.2 playground - a zero-install browser console that parses, queries, validates, serializes, and canonicalizes RDF 1.2 entirely client-side on the WebAssembly build.
• docs.rs/purrdf - API reference for the umbrella crate; each member crate links its own page.
• CHANGELOG.md - every release, with breaking changes marked.
• CONFORMANCE.md - the full conformance scoreboard and how to run each suite.
• RDF12-CANON-PROFILE.md - the purrdf-rdfc12 canonicalization profile and how it differs from RDFC-1.0.
• SPARQL-GOVERNOR-PROFILE.md - the normative charge schedule for governed execution.
• PURREMB.md - the embedding companion format behind nearest-neighbour search.
• GTS-SPEC.md - the normative graph-transport wire format.
• RELEASE.md - the release process, trusted publishing setup, and artifact verification.

Versioning and releases

The suite ships one version to crates.io, PyPI, and npm in lockstep. A version-coherence check fails the build if the version sources disagree.

From 1.0.0 the suite follows semantic versioning in full: a breaking change bumps the major version, a minor bump is additive and API-compatible, and a patch bump is bugfix-only. The changelog marks each breaking entry. Raising the minimum supported Rust version rides a minor bump and never ships in a patch release.

The one exception is the C ABI. libpurrdf's purrdf.h carries its own ABI version, currently 0.7, bumped on every exported-signature change and read back at runtime. It is versioned separately from the workspace and stays 0.x; the 1.0.0 release makes no promise about it.

Publication uses Trusted Publishing through GitHub Actions OIDC rather than a long-lived registry secret. Every package receives a GitHub build-provenance attestation and an SPDX SBOM, and the release crate set is checked on wasm32-unknown-unknown before publishing. A downloaded artifact can be verified with gh attestation verify --repo Blackcat-Informatics/purrdf. Every release is listed on the GitHub releases page.

Publication facts

Citation: PurRDF: RDF 1.2 Toolkit. Publication version 1; package version 1.0.0. Blackcat Informatics Inc., 2026. DOI: 10.67342/pkg8gpp4no/v1. Source: https://github.com/Blackcat-Informatics/purrdf.