json.diff

diff --git a/lib/Mojo/Pg/PubSub.pm b/lib/Mojo/Pg/PubSub.pm
index 4098076..5b225bb 100644
--- a/lib/Mojo/Pg/PubSub.pm
+++ b/lib/Mojo/Pg/PubSub.pm
@@ -1,10 +1,17 @@
 package Mojo::Pg::PubSub;
 use Mojo::Base 'Mojo::EventEmitter';
 
+use Mojo::JSON qw(from_json to_json);
 use Scalar::Util 'weaken';
 
 has 'pg';
 
+sub json {
+  my $self = shift;
+  $self->{json}{$_}++ for @_;
+  return $self;
+}
+
 sub listen {
   my ($self, $name, $cb) = @_;
   $self->_db->listen($name) unless @{$self->{chans}{$name} ||= []};
@@ -12,7 +19,7 @@ sub listen {
   return $cb;
 }
 
-sub notify { $_[0]->_db->notify(@_[1, 2]) and return $_[0] }
+sub notify { $_[0]->_db->notify(_json(@_)) and return $_[0] }
 
 sub unlisten {
   my ($self, $name, $cb) = @_;
@@ -37,6 +44,7 @@ sub _db {
   $db->on(
     notification => sub {
       my ($db, $name, $pid, $payload) = @_;
+      $payload = from_json $payload if $self->{json}{$name};
       for my $cb (@{$self->{chans}{$name}}) { $self->$cb($payload) }
     }
   );
@@ -52,6 +60,8 @@ sub _db {
   return $db;
 }
 
+sub _json { $_[1], $_[0]{json}{$_[1]} ? to_json $_[2] : $_[2] }
+
 1;
 
 =encoding utf8
@@ -110,6 +120,21 @@ L<Mojo::Pg> object this publish/subscribe container belongs to.
 L<Mojo::Pg::PubSub> inherits all methods from L<Mojo::EventEmitter> and
 implements the following new ones.
 
+=head2 json
+
+  $pubsub = $pubsub->json('foo', 'bar');
+
+Activate JSON encoding/decoding for these channels with L<Mojo::JSON/"to_json">
+and L<Mojo::JSON/"from_json"> for notifications sent with L</"notify"> or
+received with L</"listen">.
+
+  # Send and receive data structures
+  $pubsub->json('foo')->listen(foo => sub {
+    my ($pubsub, $payload) = @_;
+    say $payload->{bar};
+  });
+  $pubsub->notify(foo => {bar => 'I ♥ Mojolicious!'});
+
 =head2 listen
 
   my $cb = $pubsub->listen(foo => sub {...});
@@ -131,6 +156,7 @@ have.
 
   $pubsub = $pubsub->notify('foo');
   $pubsub = $pubsub->notify(foo => 'I ♥ Mojolicious!');
+  $pubsub = $pubsub->notify(foo => {bar => 'baz'});
 
 Notify a channel.