(failed but promising) attempt of generating a complex flow chart automatically from a descriptive code using graph::easy [1]. First I saved in a test file (e.g. flow.txt) the following code:

graph         { flow: south; }
node          { shape: rounded; fill: #ffff00; }
node.main     { shape: rounded; fill: #8bef91; }

[ Ale ] { class: main; } --> { start: front,0; }
    [ Barley wine],
    [ Belgian ale],
    [ Brown ale ],
    [ Dark ale ],
    [ Kölsh ],
    [ Mild ],
    [ Pale ale],
    [ Wheat beer],
    [ Old ale ]

[ Belgian ale ] -->  { start: front,0; } 
    [ Abbey ],
    [ Amber ],
    [ Blond ],
    [ Dubbel ],
    [ Flemish red],
    [ Quadrupel ],
    [ Trappist ],
    [ Tripel ]

[ Dark ale ] -->  { start: front,0; } 
    [ Stout ],
    [ Porter ]

[ Stout ] -->  { start: front,0; } 
    [ Chocolate ],
    [ Coffee ],
    [ Dry stout ],
    [ Imperial ],
    [ Milk ],
    [ Oatmeal ],
    [ Oyster ]
 
[ Pale ale ] -->  { start: front,0; } 
    [ Altbier ],
    [ American ],
    [ English bitter ],
    [ I.P.A. ],
    [ Saison ],
    [ Scotch ale ]

[ Wheat beer ] -->  { start: front,0; } 
    [ Berliner Weisse ],
    [ Dunkel wheat beer ],
    [ Hefe-Weizen ],
    [ Kristall-Weizen ],
    [ Weizen-bock ],
    [ White beer]

[ Lager ] { class: main; } --> { start: front,0; } 
    [ Bock ], 
    [ Dunkel lager], 
    [ Märzen ], 
    [ Pale lager],
    [ Schwarzbier ], 
    [ Vienna lager], 
    [ Kellerbier]
     
[ Bock ] -->  { start: front,0; } 
    [ Doppelbock ], 
    [ Eisbock ], 
    [ Maibock ], 
    [ Weizenbock ]
    
[ Pale lager ] -->  { start: front,0; } 
    [ Dortmunder ], 
    [ Dry lager], 
    [ Helles], 
    [ Pilsner], 
    [ Spezial]

[ Lambic ] { class: main; } --> { start: front,0; } 
    [Faro], 
    [Fruit], 
    [Gueuze]

and then I compiled it with (working in Linux:

graph-easy --as svg flow.txt > flow.svg