The original 0.2.0 ISO (451e058228d7cbea87b5301ae6502b6be609cf7f52cc7c9e6fb477822501389b) boots as a virtual CD-ROM but fails when attached as raw USB storage. GRUB's HFS+ hybrid uses the same HYDRA_OS label as ISO9660; dracut then selects the HFS+ partition and fails to mount the live payload. This was reproduced under OVMF with a read-only USB image and no physical disk access.

The corrected image adds native xorriso -hfsplus off to grub-mkrescue. It keeps GPT, the EFI partition and El Torito boot information, and removes HFS+/APM. The builder now rejects HFS+/APM in its inspection report.

Local file: build/artifacts/hydra-os-usb-fixed.iso
Size: 2,380,120,064 bytes
SHA256: 3a126e1a1004ba24ead66971013ba4a8468508f6fac4dcaf04aa9770cb8df7e1
Frozen payload source: ebeebc7fb1aed07a5f50bc62374365d614953dad
The ISO is local; this Git directory contains evidence, not an ISO download.

Kernel, live initramfs, squashfs and embedded build manifest match the original ISO byte-for-byte. Payload hashes were computed from the actual original and corrected ISO extents. This is a media-layout repair, not a new system payload or signed runtime update. The original artifact and release evidence remain unchanged.

Verification

python3 -m unittest discover -s tests -q passed 439 tests inside Ubuntu with Python 3.12 and OpenSSL available. Initial host runs failed in pre-existing OpenSSL-dependent updater/signature tests because OpenSSL was absent or lost from the test PATH; these were not reported as successful runs.

The same corrected ISO passed the real dev/iso-smoke.py --live-only checks in both USB and CD-ROM modes: KVM, UEFI live user and overlay root, readable squashfs, sudo, required tools, NetworkManager and Hydra network services, active greetd/labwc/foot, and normal shutdown. Each run used fresh OVMF variables and a disposable test disk. Neither invoked the installer or accessed host disks. The earlier full installation and recovery checks apply to the byte-identical system payload, not a newly repeated full installation test of this repacked ISO.

The remaining FAT12 EFI partition is unchanged. OVMF successfully starts it via USB; this does not certify detection by every physical firmware. ASUS boot-menu visibility, USB port behavior and actual laptop live boot still need physical confirmation. Secure Boot must remain disabled.

Reflash the corrected ISO using a host-native writer. For the existing NixOS setup, GNOME Disks can be run temporarily; an Etcher process inside rootless Distrobox could not elevate or write the raw USB device. Do not change SSD partitions to repair an installation USB.