add the serializer

lib/Dancer2/Plugin/JsonApi/Registry.pm

@@ -52,7 +52,8 @@ error if the type does not exist.
 =cut
 
 sub type ( $self, $type ) {
-    return $self->types->{$type} || croak "type '$type' not found";
+    return $self->types->{$type} //=
+      Dancer2::Plugin::JsonApi::Registry::Schema->new( type => $type );
 }
 
 1;

lib/Dancer2/Serializer/JsonApi.pm

@@ -0,0 +1,33 @@
+use 5.38.0;
+
+package Dancer2::Serializer::JsonApi;
+
+use Dancer2::Plugin::JsonApi::Registry;
+use Dancer2::Serializer::JSON;
+
+use Moo;
+
+has content_type => ( is => 'ro', default => 'application/vnd.api+json' );
+
+with 'Dancer2::Core::Role::Serializer';
+
+has registry => (
+    is      => 'rw',
+    default => sub { Dancer2::Plugin::JsonApi::Registry->new }
+);
+
+has json_serializer => (
+    is      => 'ro',
+    default => sub { Dancer2::Serializer::JSON->new }
+);
+
+sub serialize {
+    my ( $self, $data ) = @_;
+
+    return $self->json_serializer->serialize(
+        $self->registry->serialize(%$data) );
+}
+
+sub deserialize { ... }
+
+1;

t/serializer.t

@@ -0,0 +1,22 @@
+use Test2::V0;
+
+use JSON qw/ from_json /;
+use Dancer2::Serializer::JsonApi;
+
+my $serializer =
+  Dancer2::Serializer::JsonApi->new( log_cb => sub { warn @_ } );
+
+my $data = { 'thing' =>, { id => 2 } };
+
+my $serialized = $serializer->serialize($data);
+
+like from_json($serialized),
+  { jsonapi => { version => '1.0' },
+    data    => { id      => 2, type => 'thing' },
+  };
+
+todo 'not implemented yet' => sub {
+    is $serializer->deserialize($serialized) => $data;
+};
+
+done_testing;