Service installation¶

deploy/growhat.service expects the binary at /opt/growhat/growhat, configuration at /etc/growhat/config.toml, and a growhat system user with membership of the Pi's gpio and spi groups. Create that user, install the release binary/configuration and copy the unit into /etc/systemd/system/. The unit permits /dev/gpiochip0 and /dev/spidev0.0; adjust its DeviceAllow if the verified GPIO chip differs. Keep credentials readable only by the service user.

Then validate the unit with systemd-analyze verify, reload systemd and enable/start growhat.service. These are commissioning steps; the development smoke command performs none of them. Check logs with journalctl -u growhat.service. Preserve the last working executable before upgrading; stop the service and restore it if a release fails.