Create Custom KVM & Firecracker Root Filesystems
`heyvm` CLI ships with tools to build out the rootfs you need to spin up VMs using KVM / Firecracker.
As opposed to a traditional ISO image which is a single artifact used by virtualization stacks like `libvirtd`, KVM / Firecracker VMs combine a `rootfs` with a Kernel. Building out a Dockerfile can help you create the rootfs which you can pair with a 6.1.x kernel to create a VM.
Check out our new guide for creating your own rootfs (includes commands for doing this outside of `heyvm` as well) https://heyo.computer/guides/building-custom-kvm-images.html
Posted Jun 9, 2026, 8:33 PM UTC
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