{"slug": "show-hn-bbrv3-for-gvisor-s-netstack-visualized-in-the-browser", "title": "Show HN: BBRv3 for gVisor's netstack, visualized in the browser", "summary": "Dmitry from Apoxy has built a BBRv3 congestion control implementation for gVisor's netstack, compiled it into WASM, and made it run in the browser with visualizations from the original BBR paper. The project uses Fable 5 and GPT-5.6 Sol, conforms to the -03 draft spec, and is open-source on GitHub. An accompanying blog explains congestion control basics and BBR insights.", "body_md": "Hello HN,\n\nWe’ve built a BBRv3 congestion control implementation for gVisor’s netstack (userspace Linux TCP/IP stack implementation in Go). As part of testing it I realized we can actually compile the whole thing into WASM and run it from the browser to get some cool visualizations from the original BBR paper: [https://research.google/pubs/bbr-congestion-based-congestion...](https://research.google/pubs/bbr-congestion-based-congestion-control-2/)\n\nThe project is built using Fable 5 and GPT-5.6 Sol. I’ve manually reviewed actual BBRv3 implementation line-by-line, fixed bugs and made it to conform to -03 draft spec (well, mostly). The react/wasm bindings code was only lightly skimmed and obvious UI issues were chased out - there was a lot.\n\nIf you’d like learn more, there’s an accompanying (no pun intended) blog explaining CC basics and BBR insights: [https://apoxy.dev/blog/netstack-bbrv3](https://apoxy.dev/blog/netstack-bbrv3)\n\nThe code: [https://github.com/apoxy-dev/ccsim](https://github.com/apoxy-dev/ccsim)\n\nIf anyone has ideas what other cool things we can simulate with this stack please share!\n\nCheers, -Dmitry\n\nComments URL: [https://news.ycombinator.com/item?id=49008138](https://news.ycombinator.com/item?id=49008138)\n\nPoints: 1\n\n# Comments: 0", "url": "https://wpnews.pro/news/show-hn-bbrv3-for-gvisor-s-netstack-visualized-in-the-browser", "canonical_source": "https://ccsim.apoxy.dev", "published_at": "2026-07-22 15:15:04+00:00", "updated_at": "2026-07-22 15:22:33.415670+00:00", "lang": "en", "topics": ["artificial-intelligence", "developer-tools"], "entities": ["Apoxy", "gVisor", "BBRv3", "Fable 5", "GPT-5.6 Sol", "GitHub"], "alternates": {"html": "https://wpnews.pro/news/show-hn-bbrv3-for-gvisor-s-netstack-visualized-in-the-browser", "markdown": "https://wpnews.pro/news/show-hn-bbrv3-for-gvisor-s-netstack-visualized-in-the-browser.md", "text": "https://wpnews.pro/news/show-hn-bbrv3-for-gvisor-s-netstack-visualized-in-the-browser.txt", "jsonld": "https://wpnews.pro/news/show-hn-bbrv3-for-gvisor-s-netstack-visualized-in-the-browser.jsonld"}}