Tool: Mermaid to Unicode box art (grok-mermaid)
Simon Willison’s Weblog
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16th July 2026
Tool
Mermaid to Unicode box art (grok-mermaid)
While exploring the codebase for the newly open-sourced Grok CLI coding agent I came across xai-grok-markdown/src/mermaid.rs, a "self-contained terminal renderer for Mermaid diagrams" written in Rust.
I figured it would be fun to try that out in a browser via WebAssembly. Here's the prompt I ran in Claude Code for web (Fable 5), and this is what the resulting tool looks like:
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This is a beat by Simon Willison, posted on 16th July 2026.
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