Pele makes Mermaid diagrams fast enough to be live. So I built an ontology viewer that runs in a browser tab

Description and use

Pele delivers instant, synchronous Mermaid rendering, enabling OntoLive to quickly visualize and explore ontologies in the browser, eliminating the need for desktop tools.

Problem

Viewing ontologies requires a desktop app; large ontologies cannot be rendered all at once and exploration needs rapid redraws.

Outcome

OntoLive enables instant, interactive exploration of OWL ontologies in the browser, eliminating the need for desktop tools. Pele’s fast, synchronous rendering allows depth adjustments and live LLM-driven ontology construction with immediate visual feedback.

Workflow

• Drop an .owl or .ttl file into the browser tab
• Pele parses the file and generates Mermaid class diagram text
• Render the diagram synchronously with Pele
• Click a class to focus and adjust depth with the slider
• Pele regenerates Mermaid text and redraws the diagram instantly
• Optional: use the Sweep depth button to animate depth changes
• Optional: switch to Mermaid.js for comparison and run the Race button to benchmark

Evidence

Pele is synchronous. render() returns the SVG straight away. There is no promise to wait for.

Source

Pele has no runtime dependencies.

Source

Pele removes the second obstacle, and that removes the first.

Source

Race result: Pele 0.7 ms, Mermaid.js 205.4 ms

Source

If diagrams are this cheap, they can keep up with a language model as it types.

Source