nginx proxy manager de-dockerized

[no-systemd]

Hello everyone,
I moved NPM (nginx proxy manager) including the Debian 12 system "as is/without modifying the system" from Docker to an LXC container. The LXC container is runnig and everything is working. I even apt upgraded the system including node.js. The NPM Debian 12 system uses s6 as init system to start nginx and node server. Which is running also fine inside the unprivileged LXC container. I apt installed iptables and fail2ban and ssh.
I have fail2ban regex taking care of the nginx logs and ssh auth.
I can start "fail2ban and ssh" "service ssh start" ... etc. And its running fine.
The whole NPM system is running as is. So no big changes done to the original system from docker.
Now here is my question to the maintainers of NPM. Is there a simple way to start/stop init.d scripts in "/etc/init.d" via s6-rc? Without tampering with the init scripts in "/etc/init.d".
I am aware that i could easily init.d script nginx and nodejs and and use inittab to "supervise" "(respawn)" ...
But the purpose of my de-dockerization without touching the system is to have an easy de-dockerize path for NPM and maintain an up to date NPM LXC container image ...
I am not familiar with s6 init system and I even struggle with systemd :)
Please ignore my question if this is not the right place. I might ask that on "skarnet.org"!
Cheers.

[no-systemd]

So here is what i had to do to have sysvinit scripts starting up and gracefully exiting at system shutdown. (After reading the s6 init system manual)

root@npm-undockerized:~# cat /etc/cont-init.d/sysvinit.sh
#!/bin/bash

service syslog-ng start
service cron start
service ssh start
service fail2ban start

root@npm-undockerized:~# cat /etc/services.d/sysvinit/finish
#!/bin/bash

service ssh stop
service fail2ban stop
service cron stop
service syslog-ng stop

root@npm-undockerized:~# ls -ls /usr/sbin/{halt,init,poweroff,reboot,shutdown}
0 lrwxrwxrwx 1 root root 24 Sep 21 07:46 /usr/sbin/halt -> /run/s6/basedir/bin/halt
0 lrwxrwxrwx 1 root root 24 Sep 21 07:47 /usr/sbin/init -> /run/s6/basedir/bin/init
0 lrwxrwxrwx 1 root root 28 Sep 21 07:46 /usr/sbin/poweroff -> /run/s6/basedir/bin/poweroff
0 lrwxrwxrwx 1 root root 26 Sep 21 07:39 /usr/sbin/reboot -> /run/s6/basedir/bin/reboot
0 lrwxrwxrwx 1 root root 28 Sep 21 07:45 /usr/sbin/shutdown -> /run/s6/basedir/bin/shutdown

There might be a nicer way though.