Installation doc is outdated

[TristisOris]

this one outdated https://elephant-shed.io/doc/chapter/installation.html#installation-on-debian-and-ubuntu
sudo apt-get install postgresql-10

sudo apt-get install -t buster-backports python3-django
Reading package lists... Done
E: The value 'buster-backports' is invalid for APT::Default-Release as such a release is not available in the sources

this one works. probasbly. https://elephant-shed.io/project/ubuntu/

Setting up elephant-shed-cockpit (1.3.10.pgdg24.04+1) ...
...
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Errors were encountered while processing:
 elephant-shed-portal
 elephant-shed
needrestart is being skipped since dpkg has failed
E: Sub-process /usr/bin/dpkg returned an error code (1)

[TristisOris]

https://www.elephant-shed.io/doc/chapter/first-steps.html
Open a shell connection to the server using SSH or shellinabox https://your-server/shellinabox.

i see no way to add an external pg instance. stuck here. absolute sosna.