# NixOS Build Spec (sam-4screen-desktop)

## Disk / Boot (DO NOT BRICK WINDOWS)
Target disk: /dev/nvme0n1
- Size: 953.87 GiB (1024209543168 bytes), 2000409264 sectors
- Model: PM951 NVMe SAMSUNG 1024GB
- NVMe serial: S2FZNXAH301424
- NVMe WWID: nvme.144d-2020202020205332465a4e584148333031343234-504d393531204e564d652053414d53554e4720313032344742-00000001
- Sector size (logical/physical): 512 bytes / 512 bytes
Install target is NVMe only. Do not select /dev/sdX devices in the installer.
Device names like /dev/sdb, /dev/sdc can change across boots; always rely on UUID/label.

NOTE: GPT partition table entries may not be stored/printed in on-disk (Start sector) order.
- Do NOT rely on the order shown by some tools.
- Always identify partitions by (partition number + type + UUID/label).
- If you need the physical order, sort by the “Start” sector column (e.g. `fdisk -l` output).

Verification commands (run before formatting):
- `lsblk -o NAME,SIZE,TYPE,FSTYPE,LABEL,UUID,MOUNTPOINTS`
- `sudo fdisk -l /dev/nvme0n1` (interpret physical order by sorting on Start)
- `sudo blkid /dev/nvme0n1p1 /dev/nvme0n1p3 /dev/nvme0n1p4 /dev/nvme0n1p5`

KEEP (do not format):
- /dev/nvme0n1p1 (EFI vfat) UUID=94CC-9DA4 (~99MiB, FAT32, mounted at /boot/efi)
- /dev/nvme0n1p2 (MS reserved) (~15MiB)
- /dev/nvme0n1p3 (Windows NTFS) UUID=8294CD2994CD2111 (~503GiB)
- /dev/nvme0n1p4 (Windows recovery NTFS) UUID=6E1AA32B1AA2EEF1 (~529MiB)

WIPE + install NixOS here:
- /dev/nvme0n1p5 (currently Ubuntu ext4 /) UUID=4e99904c-ce6f-4c3c-898a-e29cfc373489 (~449GiB)

## Other attached disks (DO NOT FORMAT)
- /dev/sda (240GB) model: Patriot Burst El (KEEP)
  - /dev/sda1: Microsoft reserved partition (~15MiB)
  - /dev/sda2: NTFS label "Back Up" (keep)
- TempBackup (ext4) UUID=4f9c4bd5-fea5-408f-9370-731fc095da3f (~465GiB/500GB) (KEEP)
  - Model: WD5000BEVT-22ZAT
  - Serial: WD-WXNY08ND2684
  - NOTE: device name may appear as /dev/sdb or /dev/sdc depending on boot/USB order; identify by UUID/label/model.
- Integral300 (ext4) UUID=27febd74-20aa-4a3a-92c1-6fdd1ad7e88e (~298GiB/320GB) (mount at /data)
  - NOTE: device name may change; config always uses /dev/disk/by-uuid.
- /dev/sde (160GB) ext4 label "XPSystemDrive" (keep)

Bootloader:
- systemd-boot, using the existing EFI partition (/dev/nvme0n1p1)

## Networking
- Use NetworkManager
- Static IPv4 for wired: enp0s31f6 = 192.168.20.27/24
- Gateway: 192.168.20.1
- DNS: 192.168.20.35, 192.168.20.13

## Data drive mount
- Integral300 ext4 UUID=27febd74-20aa-4a3a-92c1-6fdd1ad7e88e
- Mountpoint on NixOS: /data (preferred)

## Desktop
- Primary compositor: Niri
- Display/login manager: greetd + tuigreet
- Session start command: `niri --session` (do not use `niri-session`)
- GPU: Intel HD 630 + NVIDIA Quadro P620
- Display appears to be driven by NVIDIA Quadro P620 (observed `/dev/fb0` on Ubuntu scan). Treat NVIDIA as primary unless proven otherwise.

## Secrets policy
- No API keys or WiFi PSKs committed to git