Beautiful Mermaid renders diagrams as SVG and ASCII

January 29, 2026
by Ryan Porter

Beautiful Mermaid, an open source diagram renderer from Craft

Beautiful Mermaid is an open source Mermaid renderer from the Craft team. Sixteen themes. SVG and ASCII. Flowcharts, sequence, class, ER, state, and charts. The source is on GitHub.

The useful part for agents is the output: a file, not a screenshot of a website.