Couldn't you replicate all of your setup with qemu microvm? Without nix I mean
Yep. What nix adds is a declarative and reproducible way to build customized OS images to boot into.
Coding Agent VMs on NixOS with Microvm.nix
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Re: Coding Agent VMs on NixOS with Microvm.nix
#12That is quite an involved setup to get a costly autocomplete going. Is that really where we are at? Just outsource convenience to a few big players that can afford the hardware? Just to save on typing and god forbid…thinking? “Sorry boss, I can’t write code because cloudflare is down.”
Keep in mind that this setup is a one-time cost. Also, a lot of the code is related to configuring it the way the author wants it (via Home Manager).
Generally speaking, once you have a working NixOS config, incremental changes become extremely trivial, safe, and easy to rollback.
Re: Coding Agent VMs on NixOS with Microvm.nix
#13[dead]
Re: Coding Agent VMs on NixOS with Microvm.nix
#14Couldn't you replicate all of your setup with qemu microvm? Without nix I mean
Yep. What nix adds is a declarative and reproducible way to build customized OS images to boot into.
Nix is the best answer to "works on my machine," which is a problem I've seen at pretty much every place I've ever worked.
Re: Coding Agent VMs on NixOS with Microvm.nix
#15I was looking for a way to isolate my agents in a more convenient way, and I really love your idea. I'm going to give this a try over the weekend and will report back.
But the one-time setup seems like a really fair investment for having a more secure development. Of course, what concerns the problem of getting malicious code to production, this will not help. But this will, with a little overhead, I think, really make development locally much more secure.
And you can automate it a lot. And it will be finally my chance to get more into NixOS :D
Re: Coding Agent VMs on NixOS with Microvm.nix
#16A pair of containers felt a bit cheaper than a VM:
https://github.com/5L-Labs/amp_in_a_box
I was going to add Gemini / OpenCode Kilo next.
There is some upfront cost to define what endpoints to map inside, but it definitely adds a veneer of preventing the crazy…
Re: Coding Agent VMs on NixOS with Microvm.nix
#17[flagged]
Precisely! There's a fundamental tension:
1. Agents need to interact with the outside world to be useful
2. Interacting with the outside world is dangerous
Sandboxes provide a "default-deny policy" which is the right starting point. But, current tools lack the right primitives to make fine grained data-access and data policy a reality.
Object-capabilities provide the primitive for fine-grained access. IFC (information flow control) for dataflow.
Re: Coding Agent VMs on NixOS with Microvm.nix
#18I there a way to make this work with macOS hosts, preferably without having to install a Linux toolchain inside the VM for the language the agent will be writing code in?
Re: Coding Agent VMs on NixOS with Microvm.nix
#19I use shellbox.dev to create sandboxes through ssh, without ever leaving the terminal
Re: Coding Agent VMs on NixOS with Microvm.nix
#20we run ~10k agent pods on k3s and went with gvisor over microvms purely for density. the memory overhead of a dedicated kernel per tenant just doesn't scale when you're trying to pack thousands of instances onto a few nodes. strict network policies and pid limits cover most of the isolation gaps anyway.
Hey @clawsyndicate I'd love to learn more about your use case. We are working on a product that would potentially get you the best of both worlds (microVM security and containers/gVisor scalability). My email is in my profile.