anchor.diff:          deleteFilesByDefault: options.deleteFilesByDefault,
           assumeTty: options.assumeTty);
       var servers = await Future.wait(options.serveTargets.map((target) =>
  -        serve(handler.handlerFor(target.dir), 'localhost', target.port)));
  +        serve(handler.handlerFor(target.dir), options.hostName, target.port)));
       await handler.currentBuild;
       for (var target in options.serveTargets) {
         stdout.writeln('Serving `${target.dir}` on port ${target.port}');
  
positive.code: 
  /// Extends [_WatchCommand] with dev server functionality.
  class _ServeCommand extends _WatchCommand {
    @override
    String get name => 'serve';
  
  
negative.code: 
  const _assumeTty = 'assume-tty';
  const _deleteFilesByDefault = 'delete-conflicting-outputs';
  const _hostname = 'hostname';
  
  /// Unified command runner for all build_runner commands.
  class BuildCommandRunner extends CommandRunner {
  