How to avoid service postgresql starting automatically

Help
1

Hi All!
I use PostGreSQL on my NixOS seldom but it is started automatically on system boot.

I would like the service not to be started automatically but rather start it manually when I need it.
How can I achieve this?

Here my current settings:

services = {
...
  postgresql = {
    enable = true;
    enableTCPIP = false;
    package = pkgs.postgresql_15;
    start = false;
    authentication = pkgs.lib.mkOverride 10 ''
    local all all trust
    host all all 127.0.0.1/32 trust
    host all all ::1/128 trust
  '';
  };
};

The following two attempts failed:

enable = false;
systemctl enable/start
Unit file postgresql.service does not exist.

wantedBy = pkgs.lib.mkForce [];
nixos-rebuild test
The option `services.postgresql.wantedBy’ does not exist.

2

i guess the option you are looking for is

systemd.services.postgresql.wantedBy

it is the thing that is generated by services.postgres
so

systemd.services.postgresql.wantedBy = lib.mkForce [ ];

could do the trick (not tested)

3

Thanks @Shawn8901 for your help.
Your trick works!

4

Alternatively set it up in a container through virtualisation.oci-containers in case there are other things you might need together with it and then just run the container when needed sudo nixos-containers start db.