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The @nixos_org@chaos.social integration tests have always been a fantastic tool - We just made them even faster and much simpler to run! 🚀 By adding a new lightweight container backend to the test driver, you can now run your suites on standard, non-KVM VMs. 👇

Here is what the new container backend brings to your NixOS workflow:

⚡ Blazing Fast Execution: How fast? Booting two machines, letting them ping each other, and tearing them down now takes ~3 seconds!
💸 Run Anywhere (Cheaper!): You no longer need bare-metal KVM-enabled hosts. Your tests can now run seamlessly on cheap, standard VMs.
🎮 GPU Testing Support: Hardware acceleration is now accessible. You can finally test GPU-dependent workloads directly inside your integration tests!

Curious how it works under the hood and how to enable it in your projects? Dive into our latest article and try it out for yourself!

🔗 Read the full breakdown here: https://nixcademy.com/posts/faster-cheaper-nixos-integration-tests-with-containers/

#NixOS #DevOps #Testing #Linux #Nix #InfrastructureAsCode #CI #Containers

Working on the @nixos_org@chaos.social test driver at #OceanSprint this week has been great. A few notable improvements for your test suites:

SSH Backdoors: Migrated to vhost-device-vsock. No more CID conflicts or extra sandbox paths needed.

Fail-Fast: qemu.forceAccel lets you force KVM/HVF and fail immediately if it’s unavailable.

Log Hygiene: The driver now uses proper log levels instead of just dumping everything to stdout.

Check out the full list of PRs here: https://applicative.systems/nixos-test-driver-manual/changelog/

#NixOS #Nix

So you created your favorite product system image, minimized it, tested its systemd-sysupdate over-the-air update capabilities, your CI automatically tests it in sandboxed virtual networks, and you are happy with it. Now your carefully engineered product wants to be deployed to a smaller embedded system without hassle? Maybe even from your Mac?

The final piece of the NixOS appliance image blog post series puzzle is here, and we are tackling one of the nastiest challenges in embedded systems and make it look easy: Cross-Compilation.

We started with the basics and progressively added advanced capabilities:

🔹 Part 1: Making "self-inflating" NixOS images that automatically resize their filesystems on first boot using systemd-repart
🔹 Part 2: Learn how to use builtin Nix capabilities to minimize images
🔹 Part 3: Implementing robust, atomic auto-updates with systemd-sysupdate
🔹 Part 4: Cross-compiling the image from any platform to any platform

If you are building IoT devices or optimized cloud images, you rarely build on the target hardware. You want to build here (e.g., a powerful x86 server or a MacBook) to deploy there (e.g., ARM64 Raspberry Pi, small RISCV board or whatever small system).

In this final guide, we provide a scalable Nix Flake architecture designed to handle this elegantly.
We move beyond simple cross-compilation hacks and show you how to:

✅ Strictly separate system configuration from build platform metadata.
✅ Automatically generate every combination of build/host platform (the Cartesian product).
✅ Build Linux images effortlessly even from macOS.

This is the blueprint for a maintainable, multi-architecture build pipeline.

👉 Read the Article: https://nixcademy.com/posts/cross-compile-nixos-images/
👉 Get the Code: https://nixcademy.com/posts/cross-compile-nixos-images/

#NixOS #Nix #DevOps #EmbeddedSystems #IoT #CrossCompilation #Linux

Should we perhaps rename the "main" branch to "initial," since "main" suggests that the others aren't important and thus discriminates against the work of some? #git #programming #social

Still relying solely on Nix flakes for input pinning? You are missing out on some seriously cool features! 🤯 Standard tools limit you to Git/Hg, force massive redownloads just to check for updates, and lack mirror support.

Enter Nixtamal! 🌟 It unlocks:
✨ Any VCS
✨ Custom freshness checks (curl an API instead of downloading 45GB!)
✨ Input patching before import
✨ BLAKE3 hashing & mirrors!

Don't stay locked in the past: https://nixcademy.com/posts/dont-let-flakes-pin-you-down-unlocking-better-inputs-with-nixtamal/ #NixOS #Nix

A slight touch of procrastination today with the @nixos_org@chaos.social language

@ariethefloof@arcanekittens.xyz All of the text is 100% hand-written. No AI was used to write the code or article text. It's just that i am a terrible painter. :-)

How @forgejo@floss.social is so much fun to use, mostly because of 2 things for me:

- it's really snappy. No waiting most of the time as it's normal on github and gitlab.
- very clean UI.

(using the forgejo at @Codeberg@social.anoxinon.de and a multiple private @forgejo@floss.social instances)

Drop-in replacement for darwin.linux-builder with Rosetta support:

If you're using nix-darwins nix.linux-builder (the QEMU-based darwin.linux-builder) on macOS, I'd like to invite you to try vzvm:

https://github.com/applicative-systems/vzvm

It runs nearly the same NixOS builder guest on Apple's Virtualization.framework instead of QEMU. The main win is Rosetta: x86_64-linux builds are translated rather than software-emulated, which came out ~2.5x faster in my benchmarks. It also boots faster and has a much smaller host closure.

It's a genuine drop-in replacement — same port, same host key, same nix.linux-builder options. Migrating is two new lines in your config. See the readme!

The longer-term goal is upstreaming into nixpkgs/nix-darwin so a vz-backed builder becomes a supported option. Feedback, bug reports, and benchmark results from other machines are very welcome!