Launch HN: Bullet (YC S26) – A Faster Coding Agent

Bullet, a Y Combinator S26 startup founded by Yale graduates Adi and Alex, launched a faster coding agent that resolves 479 out of 500 (95.8%) SWE-bench Verified tasks in one attempt, averaging 119 seconds per task and running 35–67% faster than mini-SWE-agent with Fable or Sol. The founders built Bullet after frustrations with Claude Code and Codex, incorporating model routing, targeted code search, context hygiene, efficient turns, and a feature called 'The Flash' to reduce round trips by 16% and cost by 27%.

Hi HN We’re Adi and Alex, founders of Bullet, a faster coding agent. Bullet started in a senior year dorm room at Yale. We were fresh out of working at AppLovin and Citadel, so naturally, we just knew we were going to be startup gods. We were going to use our skills optimizing stock pricing calculation speeds and agent document context to take over the world. Lo-and-behold, that year, Bullet was an AI hedge fund, a browser-use agent, synthetic financial data oof , a mobile IDE, and a bunch of other things. We wanted to build something people wanted, but it seemed like everything we built was just terrible, useless, or both. So, we decided to do something completely different, something completely out of the blue, something that no one had ever done before. Solve a problem we actually had. Over the course of six pivots, we suffered. Throughout all of our adventures, one final boss kept getting in our way. Claude Code and his little brother Codex. We were spending hours waiting for coding agents like Claude Code and Codex, and got so frustrated to the point that I downloaded the Claude Code whip. We had spent months of time waiting for six codebases-worth of useless coding agent work. Lightbulb moment. There’s nothing more noble than destroying the institutions Let’s take on Claude Code and Codex, we can do it Piece of cake And so, Bullet started off as a side project. We used the Claude Code to improve the Claude Code: 1. Model routing. Do you regret giving a task to Fable when it could have literally been done by Sonnet? 2. Targeted code + context search. We think embedding the whole repo is dumb. We also think sticking the whole context or compressed context in chat is dumb. So we do faster and better greps over both. 3. Aggressive context hygiene. Tool output is bounded, stale screenshots disappear, we don’t re-read files…the garbage never floods the model. 4. Efficient turns. Batch independent investigation, make one surgical edit, then perform one focused verification. Internal measurement showed 16% fewer round trips and 27% lower cost. 5. The Flash. We prayed to Barry Allen for speed. And thank the Flash, he gave us speed On SWE-bench Verified, Bullet resolved 479/500 95.8% in one attempt, averaging 119s per task, 35–67% faster than mini-SWE-agent + Fable/Sol depending on task. Full results and methodology here https://www.codewithbullet.com/blog/benchmark-results.html https://www.codewithbullet.com/blog/benchmark-results.html Eventually we started using it every day and never went back. Listed above were just some of the things about Claude Code that frustrated us the most, but we are constantly optimizing every day look at that, maybe we did learn something from our jobs . So do you suffer? We are here for you. We understand. Here’s the video demo https://www.youtube.com/watch?v=rWVmG5fRKgE https://www.youtube.com/watch?v=rWVmG5fRKgE Seriously speaking though, we hope that you guys try out Bullet if you are suffering with speed as much as we were, and we hope it brings you joy, rainbows, and faster responses. And if it’s terrible, let us know it’s terrible we’re masochists btw We'll be in the comments all day, you can also contact us at bullet@davidhf.com. Thanks guys for listening to the larp : try out codewithbullet.com. Again, that’s codewithbullet.com. Again, that’s codewi… P.S: we hid a code on the website, see if you can unlock the secret page at the footer, all built with Bullet Comments URL: https://news.ycombinator.com/item?id=49283063 https://news.ycombinator.com/item?id=49283063 Points: 2 Comments: 0