Ten-pin bowling in the browser in real 3D, built at the dimensions the United States Bowling Congress publishes rather than at dimensions that looked about right: 60 feet from the foul line to the head pin, 41.5 inches and 39 boards wide, ten pins on 12-inch centres in an equilateral triangle, each one lathed from the fourteen published diameters, and channels 9-1/4 inches wide. The ball is integrated from a published system of five coupled differential equations, so the hook comes from friction against a real oil pattern rather than from a scripted curve - set the revs to zero on a flat pattern and it travels exactly straight. Scoring is the USBC playing rules, diffed against an independent oracle over every reachable frame window and counted exhaustively over all 5,726,805,883,325,784,576 distinct games. Sources: the USBC Equipment Specifications and Certifications Manual and Playing Rules, the PBA oil-pattern library, a Kegel pattern sheet, Neil Stremmel's USBC work on entry angle, and Ji, Yang, Dominguez and Bester (arXiv:2210.06753) for the equations of motion. What is not published - the cross-lane shape of a pattern, the collision model, pin carry - is labelled reconstructed in CREDITS.txt and in the app. An independent implementation, not affiliated with the USBC or the PBA. Hand-written WebGL2, no libraries, no model, no credits, nothing sent anywhere.

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