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Show HN: Open source alternative to Perplexity Comet

(www.browseros.com)
281 points felarof | 1 comments | 10 Jul 25 17:33 UTC | HN request time: 1.003s | source

Hey HN, we're a YC startup building an open-source, privacy-first alternative to Perplexity Comet.

No invite system unlike bunch of others – you can download it today from our website or GitHub: https://github.com/browseros-ai/BrowserOS

--- Why bother building an alternative? We believe browsers will become the new operating systems, where we offload much bunch of our work to AI agents. But these agents will have access to all your sensitive data – emails, docs, on top of your browser history. Open-source, privacy-first alternatives need to exist.

We're not a search or ad company, so no weird incentives. Your data stays on your machine. You can use local LLMs with Ollama. We also support BYOK (bring your own keys), so no $200/month plans.

Another big difference vs Perplexity Comet: our agent runs locally in your browser (not on their server). You can actually watch it click around and do stuff, which is pretty cool! Short demo here: https://bit.ly/browserOS-demo

--- How we built? We patch Chromium's C++ source code with our changes, so we have the same security as Google Chrome. We also have an auto-updater for security patches and regular updates.

Working with Chromium's 15M lines of C++ has been another fun adventure that I'm writing a blog post on. Cursor/VSCode breaks at this scale, so we're back to using grep to find stuff and make changes. Claude code works surprisingly well too.

Building the binary takes ~3 hours on our M4 Max MacBook.

--- Next? We're just 2 people with a lot of work ahead (Firefox started with 3 hackers, history rhymes!). But we strongly believe that a privacy-first browser with local LLM support is more important than ever – since agents will have access to so much sensitive data.

Looking forward to any and all comments!

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MasterYoda ◴[11 Jul 25 11:41 UTC] No.44531006[source]▶
If this is a privacy first browser, why wasn´t Firefox used when it is much better out of the box for this approach? All security and privacy focused webbrowser use Firefox. Like Tor Browser, Mullvad Browser, LibreWolf etc.

Also, I think it is super important we have different "webbrowser engines" and that are independent from big tech companies. If we only have chromium it would be really bad and hurt use consumer really bad and also stop inovation.

We really need to support independentCbrowsers like Firefox more.

replies(2): >>44532024 #>>44532827 #
1. felarof ◴[11 Jul 25 14:54 UTC] No.44532827[source]▶
This was definitely a hard choice.

We spoke to folks who had built browser on top of webkit and they spent nearly 2years just fixing random bugs and getting sites to work. I'm sure firefox/gecko engine would probably work better than webkit, but the point still is: if we don't use chromium, a lot of work does have go into fixing website compatibility issues, adding support for extension. We're 2 person startup and chromium codebase was easier to build on top of and provides a solid baseline.

And Brave has shown that you can build a privacy-focused browser on top of chromium still.

In the agentic browser era, I think there are so many low hanging fruits on privacy which are more important to address -- sending all your sensitive data to Perplexity Comet to sell ads is a pretty bad option right now. Supporting local LLM, letting folks bring their own API keys is crucial.