BACKWARD INCOMPATILBE: '/' mapping now really means it only matches

with the root /. Current catch-all behavior is not what you want in
90% of the use case. If you really want to write a catch-all handler
you can map '/.*'

lib/Tatsumaki/Application.pm

@@ -22,6 +22,7 @@ around BUILDARGS => sub {
         my $handlers = shift @_;
         my @rules;
         while (my($path, $handler) = splice @$handlers, 0, 2) {
+            $path = qr@^/$@    if $path eq '/';
             $path = qr/^$path/ unless ref $path eq 'RegExp';
             push @rules, { path => $path, handler => $handler };
         }

t/handler/root.t

@@ -0,0 +1,31 @@
+use Plack::Test;
+use Test::More;
+use HTTP::Request::Common;
+use Tatsumaki::Application;
+
+package HelloApp;
+use base qw(Tatsumaki::Handler);
+
+sub get {
+    my $self = shift;
+    $self->write("Hello World");
+}
+
+package main;
+my $app = Tatsumaki::Application->new([ '/' => 'HelloApp' ]);
+
+test_psgi $app, sub {
+    my $cb = shift;
+    my $res = $cb->(GET "http://localhost/");
+    ok $res->is_success;
+    is $res->code, 200;
+    is $res->content, 'Hello World';
+
+    $res = $cb->(GET "http://localhost/foo");
+    is $res->code, 404;
+
+    $res = $cb->(POST "http://localhost/");
+    is $res->code, 405;
+};
+
+done_testing;