The key used to be merged into steamvr.vrsettings for good (reset at the
next start after disabling, via a marker). Now it is on only while SteamVR
runs and nothing depends on Nix to undo it:
- before each SteamVR start, the oneshot runs `install.sh
steamvr-debugger-arm`: the key's value goes to
~/.local/state/steam-frame-nix/steamvr-debugger.armed ("absent", "false",
"nofile"), the key is set (jq --indent 3, mode kept), and a runtime
drop-in $XDG_RUNTIME_DIR/systemd/user/steamvr.service.d/
50-steam-frame-nix-debugger.conf runs a /usr/bin-only restore script from
$XDG_RUNTIME_DIR/steam-frame-nix on ExecStopPost= (daemon-reload only when
newly written: once per boot). A key that is already true without .armed
is the user's own and never touched. The old marker migrates to .armed
("absent").
- when SteamVR stops, the key goes back to its previous value (removed if
it was absent, the file too if it only existed for the key) and .armed
is removed. .armed is the only trace a power loss can leave; the next
start or steam-frame-nix-cleanup resolves it.
- disabled: no unit and no drop-in at all; the orphan cleanup restores the
key once SteamVR is stopped (or leaves it to the runtime drop-in while it
runs).
A daemon-reload from a oneshot pulled in by a pending start job was tried
on dummy user units: the job survives and the new ExecStopPost= applies,
also on restart (stop, then the oneshot, then start).
checks.cleanup covers arming, re-arming, restoring and the user's own key.
`install.sh cleanup [--dry-run] (--all | --orphans [--keep <artifact>]...)`
knows every file any version wrote outside the store and Home Manager's
links, removes only what is provably its own, prints every action and
reports everything else as "left alone"; a second run changes nothing.
Only bash, coreutils, findutils, grep, sed, awk and jq (all in /usr/bin on
SteamOS), so it also works piped from curl after a rollback or with Nix gone.
- SteamVR debugger: VRWebHelper.DebuggerEnabled is put back to its value
from before (steamvr-debugger.armed; the old empty marker means "absent"
and is migrated), only while SteamVR is stopped. While it runs, a runtime
drop-in (/run/user/<uid>/systemd/user/steamvr.service.d) runs a /usr/bin-only
restore script from /run/user/<uid>/steam-frame-nix when SteamVR stops.
- icon fallback links into Breeze and their manifest (dirs only if they
held nothing else; hicolor's mtime bumped so Steam rescans).
- Firefox: the desktop profile's user.js link, older user.js links and
marker-headed copies, and the values they left in prefs.js (only with the
profile closed; deferred otherwise).
- Jellyfin: the hwdec shim entries in the Flatpak override (devices=all
only when it came with them), an empty override file, the old shim copy.
- the dashboard patches' saved state: --all only; --orphans removes just
stale *.json.tmp files.
`install.sh uninstall` runs `cleanup --all` before removing Home Manager
(replacing its own ui-patches removal) and names what is deferred;
`install.sh status` shows what `cleanup --all` would do. The flake exports
it as packages.<system>.cleanup / apps.cleanup
(`nix run github:lhns/steam-frame-nix#cleanup -- --all`), and
checks.cleanup runs it against fake home and runtime dirs: every artifact
next to look-alikes that aren't ours, --dry-run, second runs, SteamVR
running (deferral, restore script), the user's own debugger key.
Pierre Kisters