code: private static Fork fork(final String host, final Take take) {
          return new Fork() {
              @Override
              public Opt<Response> route(final Request req) throws IOException {
                  final String hst = new RqHeaders.Smart(
                      new RqHeaders.Base(req)
                  ).single("host");
                  final Opt<Response> rsp;
                  if (new EnglishLowerCase(host).string()
                      .equals(new EnglishLowerCase(hst).string())) {
                      rsp = new Opt.Single<>(take.act(req));
                  } else {
                      rsp = new Opt.Empty<>();
                  }
                  return rsp;
              }
          };
      }
docs: Make fork.
  @param host Host
  @param take Take to use
  @return Fork