Varun Mohan didn’t set out to build one of the fastest-growing AI developer tools. He just knew his company had to change, or die.
After initially betting on GPU virtualization, he saw the writing on the wall: if there was a future for his company, it would be at the AI application layer, not infra. Over a single weekend, he and his team pivoted to building Windsurf— a tool to help everyone, both technical and non-technical, write code faster and smarter.
In this conversation, Varun shares the inside story of how they pivoted at the edge of failure, trained new models from scratch, outpaced giants like GitHub Copilot, and what the future of building with AI looks like.
Apply to Y Combinator: https://ycombinator.com/apply
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Chapters (Powered by https://chapterme.co/) –
0:00 Intro
00:53 Windsurf – how big is it, where did it start?
3:00 The big pivot
6:20 Irrational optimism + uncompromising realism
7:52 Earliest versions shipped
10:26 The first customers
13:13 The transition from Codeium to Windsurf
19:45 Going up against Github Copilot
23:15 All insights depreciate; you need to keep proving yourself
26:50 Strong evals go a long way
30:15 Windsurf for hardcore engineering
31:55 Tips to get more precise changes when vibe coding
35:15 How will Windsurf evolve
38:00 Will AI become the infinite workhorse?
38:48 How does Windsurf interview candidates?
42:48 What happens if we get “just in time” software?
44:46 How many non-developers use Windsurf?
47:28 Thoughts on the GPT wrapper meme
49:17 Advice for new AI startups
51:39 Outro
