The Twenty Minute VC (20VC) · Saturday, July 4, 2026
Clay Bavor explains that Sierra, his AI company, does not engage in its own pre-training of foundational models. Instead, they focus on fine-tuning existing open-weight models, a strategic decision driven by the immense capital expense and the rapidly depreciating nature of foundational models. This approach allows Sierra to leverage the investments of larger labs and hyperscalers while still building proprietary, specialized models.
“We're not, you know, we're not doing our own pre-training. We'll leave the capital expense there to the labs and larger companies.”
“And so our calculus was for areas that are deeply capital intensive, how do we slipstream behind the investments that the labs, that hyperscalers are making, take as much as we can off the shelf while still being willing to engineer more deeply?”
“So today we have some of our own proprietary fine-tuned models, but these are fine tunes on top of open weights models. So we're not going all the way down to the, you know, mega cluster training runs.”