anchor.diff:  
       Cache.releaseLockEarly();
   
  -    // Do some early error checks for hot mode.
  -    bool hotMode = argResults['hot'];
  +    // Enable hot mode by default if ``--no-hot` was not passed and we are in
  +    // debug mode.
  +    final bool hotMode = shouldUseHotMode();
   
       if (hotMode) {
  -      if (getBuildMode() != BuildMode.debug) {
  -        printError('Hot mode only works with debug builds.');
  -        return 1;
  -      }
         if (!deviceForCommand.supportsHotMode) {
  -        printError('Hot mode is not supported by this device.');
  +        printError('Hot mode is not supported by this device. '
  +                   'Run with --no-hot.');
           return 1;
         }
       }
  
positive.code:   String get usagePath {
      Device device = deviceForCommand;
  
      String command = argResults['hot'] ? 'hotrun' : name;
  
      if (device == null)
        return command;
  
negative.code:     }
    }
  
    bool shouldUseHotMode() {
      return argResults['hot'] && (getBuildMode() == BuildMode.debug);
    }
  
    @override
    Future<int> runInProject() async {
      int debugPort;
  