anchor.diff:  
     ###### implementation
   
  -  config = mkIf cfg.enable {
  +  config = mkIf (cfg.sessions != []) {
   
       systemd.services =
   
  
positive.code: 
    };
  }
  
  
  
negative.code:   options = {
  
      services.autossh = {
  
        sessions = mkOption {
          type = types.listOf (types.submodule {
  