Mohan: AI startups should bootstrap on existing APIs unless fine-tuning on large datasets
Varun Mohan · 🕰️ The Oral History of Windsurf (ft. Varun Mohan, Scott Wu, Jeff Wang, Kevin Hou, Anshul R) · Jul 28, 2025 · at 19:08
Varun Mohan (CEO of Codeium/Windsurf) advises new AI founders on whether to train proprietary models or build on existing third-party LLM APIs.
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“Unless you are, you probably should always bootstrap on top of an existing API, right? Because like, even if you were to, the only reason why we didn't is because we knew that this product was actually buildable. Probably if we worked hard enough to train a model, we would actually be able to build a great product already. But if you're actually going out and trying to build something from scratch, unless you genuinely believe I need to fine tune on top of, you know, terabytes of data, terabyte is a very large amount of data, but like tens of gigabytes of data. Probably go out and build on top of an API and spend most of your time to make it so that you can hit that quality latency trade-off properly.”
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