Thank you @happenslol,
The code looks good and indeed addresses the issue.
But there are 2 potential issues:

1. In case there is project level log level, the PC_LOG_LEVEL variable should override that.
2. I think this won't happen, because the location in which you parse the env variable is not in the right place. I think it should be here:
   

   process-compose/src/loader/validators.go

   Lines 24 to 38 in 55d6437

   	func validateLogLevel(p *types.Project) error {
   	if p.LogLevel != "" {
   	lvl, err := zerolog.ParseLevel(p.LogLevel)
   	if err != nil {
   	if p.IsStrict {
   	return fmt.Errorf("unknown log level %s", p.LogLevel)
   	}
   	log.Warn().Msgf("Unknown log level %s defaulting to %s",
   	p.LogLevel, zerolog.GlobalLevel().String())
   	} else {
   	zerolog.SetGlobalLevel(lvl)
   	}
   	}
   	return nil
   	}

This will also allow you to reuse some of the things that already exit there.