FWIW while Karpathy was at Tesla he was basically working on the vision component. The actual driving component (using vision as an input) was originally all C++. They may have started migrating parts of the driving component from C++ to neural networks while Karpathy was there, but most of it happened after he left in 2022, with the big switch being FSD 12 in 2024. User reports from before/after FSD 12 are like night and day.
alt Hacker News
FWIW while Karpathy was at Tesla he was basically working on the vision component. The actual driving component (using vision as an input) was originally all C++. They may have started migrating parts of the driving component from C++ to neural networks while Karpathy was there, but most of it happened after he left in 2022, with the big switch being FSD 12 in 2024. User reports from before/after FSD 12 are like night and day.