VisiCalc reconstructed

I'm a bit surprised that VisiCalc did no dependency tracking. Excel, as I understand it, topologically sorts cells with dependencies and evaluates them in that order; I would have expected something similar.

Then again, back when VisiCalc debuted, it was replacing manual calculations. Compared to that, "tell the computer to recalculate until the worksheet converges" is already quite an improvement, especially if a recalculation only takes a few seconds per round.