Tesla Autopilot neural networks systematically replaced explicit C++ code
Andrej Karpathy · Andrej Karpathy: Software Is Changing (Again) · Y Combinator · Jun 19, 2025 · at 4:57
Andrej Karpathy, former Director of AI at Tesla, explains how Software 2.0 neural network models displaced traditional explicit code in the Autopilot stack.
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“As we made the autopilot better, basically the neural network grew in capability and size, and in addition to that, all the C++ code was being deleted and kind of like was And a lot of the kind of capabilities and functionality that was originally written in one point oh, was migrated to two point oh. So as an example, a lot of the stitching up of information across images from the different cameras and across time was done by neural network and we were able to delete a lot of code. And so the. Software two point oh stack and quite literally eight through the software stack of the autopilot.”
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