I made a dual-bootable NixBSD (NixOS and FreeBSD) image

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External ID

46812397

Source

HN

Company

—

Product

I made a dual-bootable NixBSD (NixOS and FreeBSD) image

Website domain

github.com

Launched

Jan. 29, 2026

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Upvotes

9

Upvotes percentile

0.461133069828722

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Fetched at

Sept. 7, 2026, 9:25 p.m.

Updated at

Sept. 7, 2026, 9:25 p.m.

Description

I've been working on getting NixBSD (Nix package manager + FreeBSD) to boot alongside NixOS on a shared ZFS pool. The result is a <2GB disk image you can try in QEMU or virt-manager.What works: - GRUB chainloads FreeBSD's bootloader - Both systems share a ZFS pool - Everything is defined in a single Nix flake - Fully reproducible builds (some dependencies are now cached on Cachix) Planned: - Support native compilation of NixBSD (currently cross-compiled on Linux) - Many shortcuts were taken to get this working, needs lots of cleanup - Add a semi-automated installer like nixos-wizard Try it: qemu-system-x86_64 -enable-kvm -m 2048 \ -bios /usr/share/ovmf/OVMF.fd \ -drive file=nixos.root.img,format=raw Login: nixos/nixos or root/toorThe hardest parts were getting mounts working at boot, making the bootloader setup idempotent, and debugging early init. This disk image could potentially work on a USB stick with a bit more work.This is very much experimental. My goal is to eventually produce a proper NixBSD installation ISO and consolidate all configuration into one repository while still consuming upstream NixBSD as a flake.Download: https://github.com/jonhermansen/nixbsd-demo/releases/tag/bui...Feel free to leave feedback here or on GitHub! Thanks!

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