Uninstall

Your apps are plain systemd units and Caddy sites, so they don't need the panel to run. Removing it leaves them serving as before; you just manage them over SSH from then on.

#Remove the panel and the agent

As root:

systemctl disable --now layer-panel layer-agent
rm /etc/systemd/system/layer-panel.service /etc/systemd/system/layer-agent.service
rm /etc/caddy/sites/_panel.caddy /usr/local/bin/layer
systemctl daemon-reload && systemctl reload caddy

#Keep these

Your apps use them:

• /opt/layer/node/: the app units run Node from there.
• /srv/apps/ and /etc/layer/apps/: the apps' builds, data and env files.
• /etc/caddy/sites/: the apps' sites.
• the app-* units in /etc/systemd/system/.

#Then, if you like

Delete the panel's own files:

rm -rf /opt/layer/releases /opt/layer/current /var/lib/layer
rm /etc/layer/secret.key

Without the key, the panel's encrypted copies of your environment variables can't be read anymore. Your apps don't need them: their variables are already in their own env files.

#Managing apps without the panel

systemctl status 'app-<app>@*'           # is it running, and which color: blue or green
journalctl -u 'app-<app>@*' -f           # its output
systemctl restart 'app-<app>@<color>'    # restart the color that's running
cat /etc/caddy/sites/<app>.caddy         # its domains