Ontologies made human-friendly

Dolfin is a modern, indentation-based language for defining ontologies, knowledge graphs, and inference rules. Write clean, readable definitions — compile to OWL/Turtle, SHACL, and more.

Why Dolfin?

Ontology engineering shouldn't require a PhD in XML. Dolfin gives you expressive power with clean syntax.

• Indentation-Based Syntax: No XML, no angle-bracket soup. Dolfin uses clean indentation like Python, making ontologies readable at a glance.
• Compiles to OWL/Turtle: Generate standards-compliant OWL ontologies in Turtle format. Full support for classes, properties, restrictions, and cardinalities.
• Built-in Inference Rules: Define match/then rules directly in your ontology. Compiles to N3 logic rules for reasoning engines.
• Package System: Organize ontologies into packages with namespaces, imports, and prefix declarations. Scale from a single file to enterprise models.
• Type-Safe Cardinalities: Express one, optional, any, or some cardinalities. Add quantifiers like at_least, at_most, and exactly with compile-time checks.
• Rust-Powered Performance: The parser is written in Rust with LALRPOP, delivering fast parsing, precise error messages, and WebAssembly support.

Where Dolfin Shines

From healthcare to finance, any domain that needs structured knowledge and automated reasoning benefits from Dolfin.

• Healthcare & Life Sciences: Model patient records, drug interactions, and clinical pathways. Dolfin's inference rules can flag contraindications or suggest treatment protocols based on patient data.
• Financial Compliance & KYC: Define regulatory concepts like beneficial ownership, risk categories, and compliance rules. Automatically classify entities and detect anomalies in transaction graphs.
• Manufacturing & Supply Chain: Model parts, assemblies, suppliers, and quality constraints. Use rules to propagate defect alerts, validate BOM structures, and optimize procurement.
• Research & Data Integration: Bridge disparate data sources with a shared ontology. Dolfin packages let teams define domain models independently, then compose them into a unified knowledge graph.
• AI & LLM Grounding: Provide structured domain knowledge to LLMs. Dolfin ontologies serve as grounding schemas for retrieval-augmented generation, reducing hallucinations.
• Enterprise Architecture: Model applications, teams, data flows, and capabilities. Define rules that enforce architectural standards and detect drift across your organization.

The Dolfin Ecosystem

A growing set of tools built around the core compiler, from IDE support to cloud APIs.

• rowl (Parser): The core Dolfin parser written in Rust with LALRPOP. Produces a typed AST with precise error diagnostics and span information.
• Turtle Generator: Compiles Dolfin AST to OWL/Turtle output. Handles class hierarchies, property restrictions, cardinalities, enums, and N3 rules.
• Python Bindings: Use Dolfin from Python via PyO3. Parse files, inspect ASTs, and integrate with data science workflows and Jupyter notebooks.
• WASM Playground: Run the Dolfin compiler directly in the browser via WebAssembly. Powers the playground on this page and can be embedded anywhere.
• VS Code Extension: Syntax highlighting, error diagnostics, and auto-completion for .dlf files. Powered by LSP backed by the Rust parser.
• REST Compile API: A lightweight HTTP service that accepts Dolfin source and returns compiled Turtle. Deploy as a microservice or sidecar.
• Pangloss: A glossary visualizer for Agrafe projects. Reads SKOS labels, alt-labels, and comments from your triple store and renders a searchable, human-friendly terminology browser.
• Eqlat: A visual query builder for deployed Agrafe ontologies. Build SPARQL queries by clicking through concepts and relations — no query syntax required, driven entirely by your schema.

Agrafe

The project editor and visualizer for Dolfin ontologies. Write schemas in the browser, explore your knowledge graph interactively, and manage all your projects from one place.

• Edit Dolfin schemas in the browser with live validation
• Visualize your ontology as an interactive knowledge graph
• Organize work into projects with multiple schemas
• Deploy as a validated triple-store endpoint — schema-enforced writes, Bearer tokens, audit logs

Pangloss

A glossary browser for your Agrafe projects. Pangloss reads the SKOS labels, alt-labels, and definitions from your ontology and turns them into a searchable, human-friendly terminology site.

• Search concepts, properties, and rules across the whole package
• Reads SKOS labels, alt-labels, and definitions straight from your triple store
• Cross-linked definitions — jump between related terms in one click
• Publish a read-only public glossary snapshot to share with your team

Eqlat

Query your ontologies visually. Eqlat turns your deployed Agrafe projects into a point-and-click query builder — no SPARQL syntax required.

• Build queries by clicking through concepts and relations
• Sparnatural-powered visual builder driven by your schema
• Browse every project you've deployed from Agrafe
• Sign in with your Agrafe account — no separate setup

Simple, transparent pricing

Start for free. Scale as your ontologies grow.

• Free: Explore Dolfin and Agrafe with no commitment.
• Starter: For teams building real knowledge graphs.
• Pro: Production workloads with full control.
• Enterprise: For organizations with custom scale, security & compliance needs.

Get in Touch

Have a question, feedback, or want to collaborate? Reach out to the Dolfin team.

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