BOS — Bread Operating System

An Arch-based, Hyprland desktop distribution that ships the bread ecosystem preconfigured. One Calamares install produces a themed, bootable Wayland desktop — no manual Arch bootstrap, no wiring up dotfiles, no per-tool bakery installs.

Design rationale and the btrfs/A-B roadmap live in DESIGN.md. This file is the practical overview: what's in the image, how to build it, and how to test it.

What you get

• Compositor: Hyprland with a native-Lua config (hyprland.lua), curated keybinds, snappy animations, blur, and pywal-driven colours on a black base.
• bread ecosystem, baked into /etc/skel from bakery-managed binaries (no network needed at install time): bread/breadd, breadbar (status bar
  • notification daemon), breadbox (launcher), breadcrumbs (Wi-Fi profiles), breadpad (notes/reminders), breadman, and the bakery package manager.
• bos-settings: a GTK4 control panel that configures every bread* app's config from a GUI (non-destructively), plus snapshot rollback and bakery updates. See below.
• Login: greetd + tuigreet → Hyprland session.
• Boot splash: Plymouth bos theme (logo + spinner, black background).
• Theming: global dark across GTK3 (Adwaita-dark), GTK4/libadwaita (color-scheme: prefer-dark), and Qt (qt5ct/qt6ct Fusion dark); Papirus-Dark icons; Bibata cursor.
• Apps: kitty, nautilus (+ gvfs), Zen browser, VLC, loupe, gnome-text-editor, gnome-calculator, file-roller, with file associations wired in mimeapps.list.
• Hardware: pipewire audio, NetworkManager, BlueZ + blueman, CUPS printing with avahi mDNS discovery, TLP power management, fwupd firmware updates.
• Resilience: btrfs + snapper + snap-pac + grub-btrfs snapshots on every pacman transaction; zram swap; ufw firewall (deny-incoming, mDNS allowed).

Repo layout

bos/
├── Cargo.toml                     # workspace (members: bos-settings)
├── bos-settings/                  # GTK4 unified settings app (Rust)
│   └── src/
│       ├── config/mod.rs          # non-destructive toml_edit config layer
│       └── ui/{widgets,window,sidebar}.rs, ui/views/*.rs
├── iso/                           # archiso profile
│   ├── profiledef.sh
│   ├── packages.x86_64            # live + installed package set
│   └── airootfs/                  # files overlaid onto the image
│       └── etc/
│           ├── skel/              # default user dotfiles (hypr, kitty, gtk, …)
│           └── calamares/         # installer config + post-install.sh
├── packaging/                     # in-house PKGBUILDs for AUR-only deps
│   ├── arch/                      # bos-settings
│   ├── calamares/
│   └── bibata/
├── .forgejo/workflows/            # CI: build + publish packages to [breadway]
├── build-local.sh                 # native ISO build for this machine
└── DESIGN.md

Building the ISO

build-local.sh builds the image natively (no container) and bakes this machine's bakery-installed bread binaries into /etc/skel:

sudo ./build-local.sh              # release-quality (xz squashfs)
sudo FAST_BUILD=1 ./build-local.sh # fast dev iteration (zstd squashfs)

The ISO lands in out/bos-<date>-x86_64.iso. The script pins SOURCE_DATE_EPOCH (reproducible UUIDs) and rewrites the [breadway] repo URL to the Tailscale-reachable Forgejo registry for the build.

Why some packages are in-house

calamares, zen-browser-bin, and bibata-cursor-theme are AUR-only. BOS keeps a PKGBUILD for each under packaging/ and republishes the built package to the [breadway] repo via a Forgejo Actions workflow (built on the hestia self-hosted runner, published with a scoped registry token). bos-settings itself publishes the same way on a v* tag.

Testing in a VM

A reusable, GPU-accelerated launcher lives at ~/bos-vm/run.sh:

~/bos-vm/run.sh install   # boot the ISO installer (target disk attached)
~/bos-vm/run.sh           # boot the installed system from the disk

It uses KVM + -cpu host, 8 GiB / 8 vCPU, and virtio-vga-gl with -display gtk,gl=on (virgl) — 3D acceleration is essential for a smooth Hyprland session in QEMU. The disk lives on NVMe (not the tmpfs /tmp) to avoid memory pressure.

bos-settings

bos-settings edits each bread* app's TOML non-destructively: it parses the file with toml_edit, changes only the keys a view exposes, and writes it back — preserving comments and any keys the UI doesn't model (calendar passwords, saved-network passwords, model paths). Views:

View	Config
bread	bread/breadd.toml — daemon, lua, modules, all adapters, events, notifications
breadbar	breadbar/style.css override
breadbox	breadbox/config.toml — launcher contexts
breadcrumbs	breadcrumbs/breadcrumbs.toml — settings, saved networks, profiles
breadpad	breadpad/breadpad.toml — settings, model + ollama, reminders, calendar
Snapshots	snapper list / rollback / delete
Packages	bakery installed list + updates
Hyprland	open config in editor + monitor list

Build standalone:

cargo build --release -p bos-settings
cargo test -p bos-settings        # includes config round-trip tests

The bread ecosystem at a glance

Tool	Role	Launch
bread / breadd	Reactive automation daemon — normalises hardware/compositor signals into events dispatched to Lua modules	runs at login
breadbar	Top status bar (workspaces, clock, stats, tray) and the notification daemon	runs at login
breadbox	Application launcher	SUPER+Space
breadpad	Notes & reminders (AI-classified, optional CalDAV sync)	SUPER+U
breadman	Package-manager UI	SUPER+M
breadcrumbs	Wi-Fi profile state machine (location-aware)	CLI / BOS Settings
bakery	CLI package manager for the ecosystem	bakery
bos-settings	Unified GTK4 control panel for all of the above + snapshots + updates	SUPER+,

Keyboard shortcuts

SUPER is the Windows/Cmd key. Press SUPER+/ at any time for this cheatsheet in-session; first boot shows a short welcome (once).

Keys	Action
SUPER+Return	Terminal (kitty)
SUPER+Space	App launcher (breadbox)
SUPER+E / SUPER+B	Files (nautilus) / Browser (zen)
SUPER+U / SUPER+M	breadpad / breadman
SUPER+, / SUPER+/	BOS Settings / keybind cheatsheet
SUPER+L / SUPER+N	Lock / log out
SUPER+Backspace	Close window
SUPER+F / SUPER+V / SUPER+T	Fullscreen / float / toggle split
SUPER+Shift+V	Clipboard history
SUPER+Tab	Last window
SUPER+Shift+S/C/P	Screenshot region→file / region→clipboard / screen→file
SUPER+arrows	Move focus
SUPER+Shift+h/j/k/l	Move window
SUPER+Shift+arrows	Resize window
SUPER+1..0	Switch to workspace 1–10
SUPER+Shift+1..0	Move window to workspace
SUPER+[ / ]	Previous / next workspace
SUPER+left/right-drag	Move / resize window with the mouse

Known limitations

• GPUs: ships the generic Mesa stack — AMD and Intel work out of the box. The NVIDIA proprietary driver is not included; NVIDIA users must install nvidia/nvidia-utils and set the usual Hyprland env vars after install.
• Virtual machines: Hyprland needs GPU acceleration to be smooth. Use virtio-vga-gl + -display gtk,gl=on (virgl); plain software rendering is noticeably laggy.
• Wayland-first: X11-only apps run through XWayland; a few may misbehave.
• Secure Boot: not configured. Boot with Secure Boot disabled, or enroll your own keys. The installer writes both an NVRAM entry and the removable EFI/BOOT/BOOTX64.EFI fallback.
• Snapshots assume btrfs: the snapper/grub-btrfs tooling expects the default btrfs subvolume layout the installer creates.

Recovery

An update broke something (system still boots): open BOS Settings → Snapshots and roll back, or pick a pre-update snapshot from the GRUB “snapshots” submenu at boot, then run snapper rollback from the booted snapshot.

The system won't boot (broken GRUB / lost EFI entry):

1. Boot the BOS ISO and open a terminal (SUPER+Return).
2. Mount the installed root and EFI, then chroot:

   mount -o subvol=@ /dev/sdXN /mnt
   mount /dev/sdXP /mnt/boot/efi      # the EFI partition
   arch-chroot /mnt
   

3. Reinstall the bootloader (the same sequence the installer uses):

   grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=BOS --recheck
   grub-install --target=x86_64-efi --efi-directory=/boot/efi --removable --recheck
   grub-mkconfig -o /boot/grub/grub.cfg
   

Firmware shows “no boot device”: select EFI/BOOT/BOOTX64.EFI from the firmware boot menu — the installer always writes that removable fallback.

Boot architecture notes

archiso keeps the kernel and initramfs outside the squashfs, so the installer stages them explicitly: a shellprocess@kernel step copies the kernel + ucode into the target /boot and writes a stock mkinitcpio preset before the native initcpio module builds the initramfs. GRUB is not installed by Calamares' bootloader/grubcfg modules (they leave the ESP empty in this layout) — post-install.sh runs grub-install (NVRAM and --removable) + grub-mkconfig instead, which is the sequence verified to boot.