According to Andrej Karpathy (@karpathy), a recent in-depth technical analysis traces a mysterious loss curve in AI model training down to a subtle bug in the PyTorch MPS backend. The issue involves the addcmul_ operation silently failing when output tensors are non-contiguous, as detailed in a longform debugging story by Elana Pearl (@ElanaPearl) [source: x.com/ElanaPearl/status/1981389648695025849]. This highlights the importance of robust backend support for GPU acceleration in machine learning frameworks, especially as developers increasingly deploy AI workloads to Apple Silicon. The incident underscores business opportunities for enhanced AI debugging tools and improved framework reliability to ensure seamless model training and deployment [source: @karpathy].