Files
punktfunk/scripts/punktfunk-scripting.service
T
enricobuehler ce8f3e9eaf feat(packaging): the plugin runner becomes a default component
WP6.1 of design/library-scanner-plugins-implementation-plan.md.

The library is a flagship surface and cannot depend on an opt-in subsystem
(design D9, closing G9): once the scanners are plugins, a host whose runner is
off comes up with an empty library and no obvious reason why. The security
posture for on-by-default was already built and shipped — LocalService on
Windows, a sandboxed systemd --user unit on Linux, the scoped plugin-token lane.

Windows (.iss): the PunktfunkScripting task is registered ENABLED and started on
a FRESH install, and left to the existing restore path on an upgrade. The
distinction is a new TaskExists probe taken before StopBunRuntimes disables
anything — TaskEnabled alone cannot tell a fresh install from an operator who
deliberately turned the runner off, and defaulting to "on" would silently switch
it back on for them.

deb/rpm: `systemctl --global enable` from the postinst/%post, guarded to first
install only so an upgrade never undoes a mask. `--global` because a maintainer
script has no user session to act on, and it is the only mechanism that makes a
--user unit on-by-default for everyone.

sysext: RPM scriptlets never run from a sysext image, so the enablement symlink
is baked in directly (/usr/lib/systemd/user/default.target.wants/). Without it
the runner would ship present-but-off on exactly the platform where an operator
is least likely to go looking for it.

Opt-out throughout is `systemctl --user mask punktfunk-scripting` — `mask`, not
`disable`, since a plain disable cannot remove a symlink under /etc or /usr. The
unit comment, both package descriptions, and the docs-site plugins page all say
so; the page also gains the Windows equivalent.

Not gated on hardware: none of this is verifiable from a Mac. The .iss change
needs an installer run (fresh + upgrade, and an upgrade with the task
deliberately disabled), and the deb/rpm/sysext changes need a package build.
2026-08-05 10:08:11 +02:00

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3.8 KiB
Desktop File

# punktfunk plugin/script runner — systemd USER unit (bun runtime, OPT-IN).
#
# Runs the operator's automation under supervision: loose files in ~/.config/punktfunk/scripts/ and
# installed `punktfunk-plugin-*` packages under ~/.config/punktfunk/plugins/. Each unit is an Effect
# fiber (a plugin restarts on failure with capped-jittered backoff; a bare script is one-shot).
# SIGTERM interrupts the whole tree STRUCTURALLY, so every plugin's scoped finalizers run before
# exit (clean deregister / preset release) — hence the generous stop timeout below.
#
# ON BY DEFAULT — the packages enable this for every user (`systemctl --global enable` from the
# .deb/.rpm scriptlets; a baked-in default.target.wants symlink in the sysext image). It used to be
# opt-in, on the reasoning that the runner does nothing until you add scripts or plugins. That
# stopped being true when the game-library scanners became plugins: the library is a flagship
# surface, and a host whose runner is off now comes up with an empty library and no obvious reason
# why (design/library-scanner-plugins.md D9).
#
# It remains opt-OUT, per user:
# systemctl --user mask punktfunk-scripting
# (`mask`, not `disable` — a plain disable cannot remove a symlink that lives in /etc or /usr.)
#
# Auto-wired like the console: a plugin's connect() reads the host's SCOPED plugin token + identity
# cert from ~/.config/punktfunk/{plugin-token,cert.pem} (written by the host's `serve`) — no env
# editing. The plugin token authorizes the plugin surface but not hook registration or pairing
# administration; a script that needs the admin surface sets PUNKTFUNK_MGMT_TOKEN explicitly.
[Unit]
Description=punktfunk plugin/script runner
Documentation=https://git.unom.io/unom/punktfunk
# Plugins talk to the host's loopback mgmt API; order after it. Soft (ordering only, no Requires):
# the runner supervises each unit with backoff, so a plugin started before the host simply retries.
After=punktfunk-host.service
[Service]
Type=simple
ExecStart=/usr/bin/punktfunk-scripting
Restart=on-failure
RestartSec=2
# Deliver the stop signal to the runner process itself (it orchestrates the structural shutdown of
# its unit fibers), and give it room to run their finalizers before the cgroup is reaped.
KillMode=mixed
KillSignal=SIGTERM
TimeoutStopSec=30
# Sandbox: free hardening for well-behaved plugins. The filesystem is read-only outside the home
# directory (ReadWritePaths keeps plugin state, download dirs, and ~/.config/punktfunk writable);
# no setuid re-escalation; sockets limited to what automation actually uses (loopback mgmt API,
# LAN/IPv6 webhooks, unix sockets). A plugin that must write OUTSIDE $HOME (e.g. a library on
# another mount) gets a drop-in:
# systemctl --user edit punktfunk-scripting → [Service]\nReadWritePaths=/mnt/games
# NOTE: the mount-namespace options (ProtectSystem) need unprivileged user namespaces for a
# *user* unit; on kernels/distros that restrict those, drop them via the same drop-in.
#
# PrivateTmp is deliberately OFF (field report 2026-08-03, the VirtualHere plugin). A plugin's
# whole job is integrating with things already running on this box, and on Linux those talk over
# /tmp: VirtualHere's client IPC is the FIFO pair /tmp/vhclient + /tmp/vhclient_response, and X11
# is /tmp/.X11-unix. A private /tmp namespace hides all of it — the plugin launches the vendor
# binary fine and then cannot reach the daemon behind it, which presents as an unexplained error
# that no amount of config fixes (the operator's own shell works, because that has the real /tmp).
# ReadWritePaths=/tmp puts the write bit back that ProtectSystem=strict takes away.
NoNewPrivileges=yes
PrivateTmp=no
ProtectSystem=strict
ReadWritePaths=%h /tmp
RestrictAddressFamilies=AF_UNIX AF_INET AF_INET6
[Install]
WantedBy=default.target