JankHunter

Canvas and WebGL apps can look correct in a screenshot while a sprite stutters, a HUD jumps after a font loads, or an object disappears for a few frames. JankHunter records a repeatable Playwright scenario, tracks selected visual elements across frames, and runs deterministic detectors for jitter, layout jumps, flicker, vanishing elements, and stutter. It sends defect evidence and source to Muse Spark for a constrained patch proposal, then rebuilds and reruns the same scenario on an isolated Git branch. A patch is kept only when the measured severity drops and no new defect types appear.