Anvanka visual is great! It was my first love in this space, and still use it a ton whenever making a point.
More recently I also found a visualisation by Robert Kieffer, which I prefer for actually cataloguing stuff and getting ideas for what to consider trying to cut out next in a contribution. It also uses a faster API strategy, but for Anvanka's the slower logic actually helps emphasize the issue. Darn those optimisations!
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