anchor.diff:  
   class FuchsiaDeviceCommandRunner {
     final String _address;
  -  final String _buildDir;
  -
  -  FuchsiaDeviceCommandRunner(this._address, this._buildDir);
  +  final String _sshConfig;
  +
  +  FuchsiaDeviceCommandRunner(this._address, this._sshConfig);
   
     Future<List<String>> run(String command) async {
  -    final String config = '$_buildDir/ssh-keys/ssh_config';
  -    final List<String> args = <String>['ssh', '-F', config, _address, command];
  +    final List<String> args = <String>['ssh', '-F', _sshConfig, _address, command];
       printTrace(args.join(' '));
       final ProcessResult result = await processManager.run(args);
       if (result.exitCode != 0) {
  
positive.code:       abbr: 'l',
        defaultsTo: false,
        help: 'Lists the running modules. ');
      argParser.addOption('name-override',
        abbr: 'n',
        help: 'On-device name of the application binary.');
      argParser.addOption('target',
        abbr: 't',
        defaultsTo: bundle.defaultMainPath,
        help: 'Target app path / main entry-point file. '
              'Relative to --gn-target path, e.g. lib/main.dart.');
    }
  
    @override
  
negative.code:       abbr: 'b',
        defaultsTo: null,
        help: 'Fuchsia build directory, e.g. out/release-x86-64.');
      argParser.addOption('dot-packages',
        abbr: 'd',
        defaultsTo: null,
        help: 'Path to the mod\'s .packages file. Required if no'
              'GN target specified.');
      argParser.addOption('gn-target',
        abbr: 'g',
        help: 'GN target of the application, e.g //path/to/app:app.');
  