Tatsumaki - Non-blocking web framework based on Plack and AnyEvent


  ### app.psgi
  use Tatsumaki::Error;
  use Tatsumaki::Application;
  use Tatsumaki::HTTPClient;
  use Tatsumaki::Server;

  package MainHandler;
  use parent qw(Tatsumaki::Handler);

  sub get {
      my $self = shift;
      $self->write("Hello World");

  package FeedHandler;
  use parent qw(Tatsumaki::Handler);

  use JSON;

  sub get {
      my($self, $query) = @_;
      my $client = Tatsumaki::HTTPClient->new;
      $client->get("$query", $self->async_cb(sub { $self->on_response(@_) }));

  sub on_response {
      my($self, $res) = @_;
      if ($res->is_error) {
      my $json = JSON::decode_json($res->content);
      $self->write("Fetched " . scalar(@{$json->{entries}}) . " entries from API");

  package StreamWriter;
  use parent qw(Tatsumaki::Handler);

  use AnyEvent;

  sub get {
      my $self = shift;

      my $try = 0;
      my $t; $t = AE::timer 0, 0.1, sub {
          $self->stream_write("Current UNIX time is " . time . "\n");
          if ($try++ >= 10) {
              undef $t;

  package main;

  my $app = Tatsumaki::Application->new([
      '/stream' => 'StreamWriter',
      '/feed/(\w+)' => 'FeedHandler',
      '/' => 'MainHandler',
  return $app->psgi_app;

And now run it with:

  plackup -s Twiggy app.psgi


This is considered as alpha quality software. Most of the stuff are undocumented since it's considered unstable and will likely to change. You should sometimes look at the source code or example apps in eg directory to see how this thing works.

Feel free to hack on it and ask me if you have questions or suggestions at IRC: #plack on


Tatsumaki is a toy port of Tornado for Perl using Plack (with non-blocking extensions) and AnyEvent.

It allows you to write a web application that does a immediate response with template rendering, IO-bound delayed response (like fetching third party API or XML feeds), server push streaming and long-poll Comet in a clean unified API.


When asynchronous is declared in your application, you need a PSGI server backend that supports psgi.streaming response style. If your application does server push with stream_write, you need a server that supports psgi.nonblocking (and psgi.streaming) as well.

Currently Tatsumaki asynchronous application is supposed to run on Twiggy, Feersum, Corona and POE::Component::Server::PSGI.

If asynchronous is not used, your application is supposed to run in any PSGI standard environments, including blocking multiprocess environments like Starman or Starlet.


Tatsumaki is a Japanese for Tornado. Also, it might sound familiar from "Tatsumaki Senpuukyaku" of Ryu from Street Fighter II if you loved the Capcom videogame back in the day :)


Tatsuhiko Miyagawa <>


This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.


AnyEvent Plack PSGI