OntoLogos

A modular Rust ontology reasoner in early development.

Display name: OntoLogos · Crates: ontologos-* · CLI binary: ontologos

v0.3 (today): RDFS materialization via ontologos-rdfs, plus OWL parsing, profile detection, and the in-memory model from v0.2.

Planned: OWL RL/EL reasoning (v0.4–v0.5), explanations (v0.6), Python bindings (v0.9).

If you need OWL classification today, use Protégé with HermiT or ELK. If you want to embed a Rust ontology graph, load OWL files, or evaluate the architecture, start below.

What works in v0.3

Feature	Status
IRI intern pool, entity registry, axiom store	Available
`OntologyBuilder` programmatic construction	Available
JSON snapshot v2 (`to_json` / `from_json`)	Available
Axiom indexes (subclass, subproperty, equivalence, …)	Available
OWL file loading (`.owl`, `.rdf`, `.ttl`, `.ofn`)	Available
Profile detection (EL / RL / QL / DL)	Available
RDFS materialization (TBox rules)	Available
`ontologos profile` CLI	Available
`ontologos materialize` CLI	Available
OWL RL / EL reasoning	v0.4–v0.5
`classify` CLI (RDFS)	Available
`explain` CLI	v0.6 (see ROADMAP)
Python bindings (full API)	v0.9

Install (library)

Requires Rust 1.88+.

From crates.io:

[dependencies]
ontologos-core = "0.3.0"
ontologos-parser = "0.3.0"
ontologos-profile = "0.3.0"
ontologos-rdfs = "0.3.0"

From this repository:

git clone https://github.com/eddiethedean/ontologos.git
cd ontologos
./benchmarks/scripts/download.sh   # for Pizza corpus examples

API reference: docs.rs/ontologos-core · parser · profile · rdfs

Python: pip install ontologos is an alpha placeholder only — use Rust crates for v0.3 workflows. See crates/ontologos-py/README.md.

Quick start (5 minutes)

Builder + JSON

cargo run -p ontologos-core --example pizza_builder

use ontologos_core::{Error, Ontology};

fn main() -> Result<(), Error> {
    let ontology = Ontology::builder()
        .class("http://example.org/Pizza")?
        .class("http://example.org/Food")?
        .subclass_of("http://example.org/Pizza", "http://example.org/Food")?
        .build()?;

    let json = ontology.to_json()?;
    let restored = Ontology::from_json(&json)?;
    assert_eq!(restored.axiom_count(), 1);
    Ok(())
}

Load OWL + materialize (v0.3)

./benchmarks/scripts/download.sh
cargo build -p ontologos-cli --release
./target/release/ontologos materialize benchmarks/data/family.owl
./target/release/ontologos profile benchmarks/data/pizza.owl

use ontologos_parser::load_ontology;
use ontologos_rdfs::RdfsEngine;

let mut ontology = load_ontology(path)?;
let report = RdfsEngine::new().materialize(&mut ontology)?;

Load OWL + detect profile

Profile classification uses mapped TBox shapes; diagnostics may list constructs seen in the source but not stored in core — see docs/guides/profile-detection.md.

Or run: cargo run -p ontologos-parser --example load_and_profile

Workspace

Crate	Description	Status
`ontologos-core`	Core data model, ontology graph, and reasoner API	v0.3
`ontologos-parser`	OWL/RDF parsers (horned-owl integration)	v0.3
`ontologos-profile`	OWL profile detection and diagnostics	v0.3
`ontologos-rdfs`	RDFS reasoning engine	v0.3
`ontologos-rl`	OWL RL forward-chaining rules	Stub
`ontologos-el`	OWL EL classification	Stub
`ontologos-query`	Query interface over classified ontologies	Stub
`ontologos-explain`	Proof graphs and explanation export	Stub
`ontologos-cli`	`ontologos` command-line tool	Partial (`profile`, `materialize`, `classify` RDFS)
`ontologos-conformance`	HermiT-ported conformance tests (workspace-only)	Dev harness
`ontologos-py`	Python bindings via PyO3	Stub

v0.3.0 publishes ontologos-core, ontologos-parser, ontologos-profile, and ontologos-rdfs to crates.io.

CLI

cargo build -p ontologos-cli --release
./target/release/ontologos profile benchmarks/data/pizza.owl
./target/release/ontologos materialize benchmarks/data/family.owl
./target/release/ontologos classify benchmarks/data/family.owl

classify runs RDFS materialization in v0.3; OWL EL/RL classification and explain ship in v0.5/v0.6 — see ROADMAP.md.

Documentation

Section	Link
Getting started	docs/README.md
Guides	Load OWL · Profile detection · Security
Reference	Errors · CLI · JSON v2
Project	ROADMAP · CHANGELOG · CONTRIBUTING · FAQ

License

Licensed under either of Apache License, Version 2.0 or MIT license at your option.

ontologos-core 0.3.0