Re: FDW API / flow charts for the docs?

I would be more inclined to let GraphViz into the process than Dia; the
former fits *much* better into a Make-based process.

It is worth observing that there are schema diagramming systems (SchemaSpy
is mighty likable) that build diagrams using GraphViz. We have integrated
this into internal deployments at Afilias.

Rod Taylor's autodoc tool has some minimal Dia support, but it lacks the
ability to do layout; if you use Dia output, you'll have to manually drag
things around to have the tables *not* all atop one another. I'm a little
surprised Dia hasn't integrated in GraphViz to help with that; note that
the MacOS diagram tool OmniGraffle (proprietary, considered quite good,
competitive with Visio) uses GraphViz to help do automatic object layout.
That this is integrated inside an interactive GUI app is pretty wild/cool.

I'd think it a fine idea to add rules for .dot files (the usual GraphViz
language/format to describe graphs) to the PG Make rules.