We Put an L7 Firewall in the Kernel for Nanosecond Decisions
We built a Layer 7 firewall that runs directly in the Linux kernel using eBPF, allowing policies written in JavaScript to execute in nanoseconds. By moving decision-making from userspace proxies to the NIC driver, we eliminate costly data copying and context switches. This approach enables blocking malicious traffic like specific User-Agents before it ever touches the network stack, offering massive performance gains without requiring rebuilds or restarts.
It's the cheapest drop Linux has: the kernel spends nothing on traffic we were going to reject anyway.
- NitpickLawyer
I try to get past the claudisms if the subject is interesting, in the hopes of learning something new, and this article had many such claudisms throughout, but it was an interesting read nonetheless. It could have been much shorter, but hey... The exception to acceptable signal to claudisms level for me was one of the later paragraphs:
> The staged rollout is the honest way to ship something that runs at XDP: each stage widens the traffic it sees, and each stage generates the numbers for the next one.
I see this so often nowadays, with claude trying to be "honest" and all that it really spoils the article for me. Using tools is fine, but at least have a human skim it and remove the really obnoxious and useless parts.
Something like this would have sufficed: "For the moment we're rolling it out in stages, and each stage will inform our next steps".
- alexdns
You didnt put anything anywhere you just vibe slopped XDP code the same way you vibe slopped your blog post
- Trev123
It's fun to see how people end up using eBPF, but it feels like this was an LLM generated post (my apologies if I'm mistaken). It doesn't feel as fun reading a post generated by an LLM - it often feels more long winded, many short sentences and over use of certain phrases.