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ericpauley07/31/20253 repliesview on HN

One of the coolest things about gVisor to me is that it's the ultimate implication of core computer engineering concepts like "the OS is just software" and "network traffic is just bytes". It's one thing to learn these ideas in theory, but it's another altogether to be able to play with an entire network stack in userspace and inject arbitrary behavior in the OSI stack. It's also been cool to see what companies like Fly.io and Tailscale can do with complete flexibility in the network, enabled by tools like gVisor.


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quotemstr07/31/2025

Just wait until you read about Wine or captive NDIS. You'll probably enjoy User Mode Linux most of all.

The concept of an OS still makes sense on a system with no privilege level transitions and a single address space (e.g. DOS, FreeRTOS): therefore, mystical low level register goo isn't essential to the concept.

The boundary between the OS is a lot more porous and a lot less arcane than people imagine. In the end, it's just software.

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leetrout07/31/2025

How does Fly use gVisor?

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sidewndr4607/31/2025

I'm trying to understand the point you're making here but don't really get it. The OS is just software, in most circumstances. Most modern OS require at least one binary blob that has to be sent to some hardware device. This is mostly because the the device manufacturer didn't want to include NVRAM and at the end of the day is usually just software as well.

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