Making a Legend/Key in GraphViz

Question

I’d like to include a legend or key in my GraphViz diagram. I’m having trouble figuring out what code to use, though. I also want to put it in a corner, but the only coord I

Answer 1

I had some luck with the following. I didn't like how wide it was, but otherwise it worked.

   subgraph cluster1 {
        label = "Legend" ;
        shape=rectangle ;
        color = black ;
        a [style=invis];
        b [style=invis] ;
        c [style=invis] ;
        d [style=invis] ;
        c -> d [label="only ts", style=dashed, fontsize=20] ; 
        a -> b [label="ts and js", fontsize=20] ;
        gui -> controller [style=invis] ;
        view -> model [style=invis] ;
        builtins -> utilities [style=invis] ;

        gui [style=filled, fillcolor="#ffcccc"] ;
        controller [style=filled, fillcolor="#ccccff"] ;
        view [style=filled, fillcolor="#ccffcc"] ;
        model [style=filled, fillcolor="#ffccff"] ;
        builtins [style=filled, fillcolor="#ffffcc"] ;
        utilities ;
        "external libraries" [shape=rectangle] ;
    }

The result was