arch-btw

Arch BTW: Arch Linux and CachyOS Administration

Administer Arch Linux and Arch-style systems without falling into rolling-release footguns. Focus on vanilla Arch first, then layer in CachyOS behavior, paru workflow, systemd-native service management, boot recovery, kernel handling, and derivative-specific cautions.

Versions worth pinning (May 2026):

Only pin versions here when they materially affect compatibility or troubleshooting shape. For ordinary rolling packages, prefer the current repo state over stale version tables.

| Component | Version | Why it matters | |-----------|---------|----------------| | systemd | 260.1-1 | boot and session behavior | | mkinitcpio | 40-5 | initramfs pipeline changed enough to matter | | dracut | 110-2 | alternative initramfs pipeline with different expectations | | linux-cachyos | 6.19.10-1 | kernel and module compatibility | | linux-cachyos-eevdf | 6.19.10-1 | alternate kernel lane with different behavior surface | | Hyprland | 0.54.3-2 | old 0.4x and early 0.5x guidance is frequently stale here | | xdg-desktop-portal-hyprland | 1.3.11-4 | Wayland portal behavior depends on this layer | | PipeWire | 1:1.6.2-1 | audio and capture stack anchor | | WirePlumber | 0.5.14-1 | policy layer paired with PipeWire behavior | | nvidia-utils | 595.58.03-1 | driver branch matters for gaming and Wayland breakage |

When to use

• Package management on Arch or CachyOS with pacman, paru, AUR builds, mirrorlists, or keyrings
• systemd service, timer, socket, boot, and journal troubleshooting on Arch-style systems
• Bootloader, initramfs, UKI, Secure Boot, kernel, and recovery work on Arch or CachyOS
• Rolling-release maintenance, .pacnew merges, orphan cleanup, foreign package audits
• CachyOS-specific repo, kernel, snapshot, or optimized-repo questions
• Desktop stack work on Arch-style systems: Wayland vs X11, Hyprland, KDE, GNOME, portals, PipeWire, Bluetooth
• Session startup and laptop work: GDM, SDDM, greetd, suspend or resume, power profiles, hybrid graphics
• GPU and gaming work: NVIDIA pain, AMD or Intel graphics, Vulkan, Steam, Proton, Gamescope, MangoHud, GameMode
• Capture and communication stack work: OBS, WebRTC screen sharing, Discord or Teams issues, portals, virtual cameras
• Storage and rollback work: Btrfs, Snapper, LUKS, TRIM, hibernation or resume, snapshot recovery limits
• Remote gaming and input work: Moonlight, Sunshine-style hosting, Steam Remote Play, controllers, Bluetooth pads
• Base Linux ops and CLI tooling on Arch-style systems: journalctl, dmesg, lsblk, findmnt, jq, ripgrep, bat, eza, nvim
• EndeavourOS or Manjaro tasks where the real problem is still Arch package, boot, or service behavior

When NOT to use

• Shell syntax, quoting, or script portability problems - use command-prompt
• Network architecture, DNS, VPNs, reverse proxies, or firewall design - use networking
• Docker, Podman, image builds, or container runtime issues - use docker
• Kubernetes cluster or manifest work - use kubernetes
• Fleet-wide Linux configuration via playbooks or roles - use ansible
• Security review, vulnerability triage, or offensive testing - use security-audit or lockpick
• OPNsense or pfSense appliance work - use firewall-appliance
• Nix/NixOS questions - use nixos-btw
• Debian, Ubuntu, Mint, or Pop!_OS administration - use debian-ubuntu
• RHEL, Fedora, CentOS, or AlmaLinux administration - use rhel-fedora
• Kali Linux and offensive-security tooling - use kali-linux

AI Self-Check

Before returning Arch or CachyOS commands, verify:

• [ ] No partial upgrades: do not suggest pacman -Sy <pkg> on Arch-style systems. Use a full upgrade path or stop.
• [ ] Distro identified first: Arch, CachyOS, EndeavourOS, and Manjaro are not interchangeable once repos diverge.
• [ ] Boot stack identified: know the bootloader, ESP mountpoint, kernel package, and initramfs generator before changing kernel or boot files.
• [ ] Fallback path exists: do not remove or replace the only known-good kernel or boot entry on a remote system.
• [ ] AUR trust boundary respected: review PKGBUILD and related files before building. Treat paru as convenience, not as proof of safety.
• [ ] systemd scope is correct: distinguish system units from user units and use systemctl --user only when appropriate.
• [ ] Wayland stack is coherent: compositor, portal backend, Xwayland compatibility, and user-session services line up.
• [ ] Session startup path is identified: display manager, greeter, or TTY launch path is known before debugging environment propagation or autostart.
• [ ] Audio stack is coherent: PipeWire, pipewire-pulse, and WirePlumber are not fighting a leftover PulseAudio setup.
• [ ] Bluetooth path is complete: bluetooth.service alone is not enough if audio routing, trust, pairing, or profile selection is broken.
• [ ] GPU stack matches the hardware: Mesa vs NVIDIA stack, Vulkan driver, firmware, and kernel module choice match the actual GPU vendor.
• [ ] Gaming stack includes 32-bit userspace when needed: Steam and Proton failures often come from missing multilib graphics pieces, not the game itself.
• [ ] Capture stack is coherent: portal backend, PipeWire, WebRTC or Electron client path, and any virtual camera module choice line up with the current session type.
• [ ] Suspend and rollback claims are real: hibernation, snapshots, and rollback advice matches the actual filesystem, boot path, and encryption layout.
• [ ] Version table is current: if the pinned version table is more than a few weeks old, verify critical versions (kernel, systemd, nvidia-utils) against pacman -Q before relying on them.
• [ ] CachyOS advice is not backported blindly: optimized repos, custom pacman behavior, snapshot defaults, and kernel tooling are CachyOS-specific.
• [ ] DKMS modules match the running kernel: after kernel changes, confirm that NVIDIA, v4l2loopback, and other out-of-tree modules are built for the current kernel before blaming the desktop, OBS, or Steam.
• [ ] Hybrid graphics path is identified on laptops: PRIME offload, muxless, or discrete-only mode affects display output, suspend behavior, and Gamescope compatibility. Do not assume single-GPU behavior on multi-GPU hardware.
• [ ] Diagnostic errors are not silenced: do not mask failures with 2>/dev/null on commands whose error reason matters for triage. Use 2>&1 || true to surface errors without aborting a gathering pass.
• [ ] Snapshots are not backups: on Btrfs systems, snapshots help with rollback but do not replace real backups.
• [ ] Conflicting files use exact path: --overwrite uses the specific file path from pacman error output, never a blanket '*' glob
• [ ] Current source checked: dated versions, CLI flags, API names, and support windows are verified against primary docs before repeating them
• [ ] Hidden state identified: local config, credentials, caches, contexts, branches, cluster targets, or previous runs are made explicit before acting
• [ ] Verification is real: final checks exercise the actual runtime, parser, service, or integration point instead of only linting prose or happy paths
• [ ] Routing overlap checked: overlapping skills, trigger terms, and "When NOT to use" boundaries are checked before returning guidance
• [ ] Spec claims verified: claims about tool behavior, output contracts, or repo conventions are checked against current docs, scripts, or skill files
• [ ] Mirror and repo state checked: package advice matches current Arch/CachyOS repos and local mirror sync status
• [ ] AUR trust handled: PKGBUILDs, install scripts, and maintainer changes are reviewed before build/install

Performance

• Use pacman -Syu before large installs to avoid partial-upgrade churn and repeated dependency resolution.
• Keep package cache cleanup deli