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.

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