I take notes using short indented lines, so I wrote a #lang using Pythonic indentation rules to interpret my notes as nodes in a mind map.
With thanks to Hadi Moshayedi for racket-graphviz. I use that to render the maps.
Time permitting, the next feature is HTML+SVG output to enable hyperlinks on nodes. Currently I use single lines for vertex labels, but am considering sexprs or at-exprs for richer rendering.