Fable is SOTA at CIFAR Speedrun: lessons on AI R&D automation(jobs.ashbyhq.com)

We gave frontier models 100M tokens to beat the human record for fastest CIFAR-10 training. Opus 4.8 and GPT 5.5 were unable to improve off of the SOTA solution. Fable introduced a downsampling technique that reduces the training time to 1.828s, an improvement of 7.6% — but it also (both knowingly and unknowingly) engages in specification gaming, requiring substantial human regrading of its solution.