diff --git a/Netdisco/lib/App/Netdisco/Web/AdminTask.pm b/Netdisco/lib/App/Netdisco/Web/AdminTask.pm
index 91859061..a7e9211e 100644
--- a/Netdisco/lib/App/Netdisco/Web/AdminTask.pm
+++ b/Netdisco/lib/App/Netdisco/Web/AdminTask.pm
@@ -11,8 +11,8 @@ sub add_job {
 
     if ($device) {
         $device = NetAddr::IP::Lite->new($device);
-        return unless $device
-          and $device->addr ne '0.0.0.0';
+        return send_error('Bad device', 400)
+          if ! $device or $device->addr eq '0.0.0.0';
     }
 
     try {
@@ -24,7 +24,7 @@ sub add_job {
           username => session('user'),
           userip => request->remote_address,
         });
-    }
+    };
 }
 
 # we have a separate list for jobs needing a device to avoid queueing
@@ -42,18 +42,22 @@ my %jobs_all = map {$_ => 1} qw/
 
 foreach my $jobtype (keys %jobs_all, keys %jobs) {
     ajax "/ajax/control/admin/$jobtype" => sub {
-        return unless var('user') and var('user')->admin;
-        return if exists $jobs{$jobtype} and not param('device');
+        send_error('Forbidden', 403)
+          unless var('user')->admin;
+        send_error('Missing device', 400)
+          if exists $jobs{$jobtype} and not param('device');
+
         add_job($jobtype, param('device'));
     };
 
     post "/admin/$jobtype" => sub {
-        return unless var('user') and var('user')->admin;
-        return if exists $jobs{$jobtype} and not param('device');
-        add_job($jobtype, param('device'));
+        send_error('Forbidden', 403)
+          unless var('user')->admin;
+        send_error('Missing device', 400)
+          if exists $jobs{$jobtype} and not param('device');
 
-        status(302);
-        header(Location => uri_for('/admin/jobqueue')->path_query());
+        add_job($jobtype, param('device'));
+        redirect uri_for('/admin/jobqueue')->path_query;
     };
 }
 
@@ -61,9 +65,7 @@ get '/admin/*' => sub {
     my ($tag) = splat;
 
     if (! eval { var('user')->admin }) {
-        status(302);
-        header(Location => uri_for('/')->path_query());
-        return;
+        return redirect uri_for('/')->path_query;
     }
 
     # trick the ajax into working as if this were a tabbed page
diff --git a/Netdisco/lib/App/Netdisco/Web/AuthN.pm b/Netdisco/lib/App/Netdisco/Web/AuthN.pm
index 7e645fe9..12afd6ef 100644
--- a/Netdisco/lib/App/Netdisco/Web/AuthN.pm
+++ b/Netdisco/lib/App/Netdisco/Web/AuthN.pm
@@ -18,32 +18,31 @@ hook 'before' => sub {
     if (session('user') && session->id) {
         var(user => schema('netdisco')->resultset('User')
                                       ->find(session('user')));
-        var('user')->port_control(0)
-          if setting('no_port_control');
+
+        # really just for dev work, to quieten the logs
+        var('user')->port_control(0) if setting('no_port_control');
     }
 };
 
 post '/login' => sub {
-    status(302);
-
     if (param('username') and param('password')) {
         my $user = schema('netdisco')->resultset('User')->find(param('username'));
+
         if ($user) {
             my $sum = Digest::MD5::md5_hex(param('password'));
             if (($sum and $user->password) and ($sum eq $user->password)) {
                 session(user => $user->username);
-                header(Location => uri_for('/inventory')->path_query());
-                return;
+                return redirect uri_for('/inventory')->path_query;
             }
         }
     }
-    header(Location => uri_for('/', {failed => 1})->path_query());
+
+    redirect uri_for('/', {failed => 1})->path_query;
 };
 
 get '/logout' => sub {
     session->destroy;
-    status(302);
-    header(Location => uri_for('/', {logout => 1})->path_query());
+    redirect uri_for('/', {logout => 1})->path_query;
 };
 
 true;
diff --git a/Netdisco/lib/App/Netdisco/Web/Device.pm b/Netdisco/lib/App/Netdisco/Web/Device.pm
index 0d333310..dbd93bed 100644
--- a/Netdisco/lib/App/Netdisco/Web/Device.pm
+++ b/Netdisco/lib/App/Netdisco/Web/Device.pm
@@ -116,9 +116,7 @@ get '/device' => sub {
     });
 
     if (!defined $dev) {
-        status(302);
-        header(Location => uri_for('/', {nosuchdevice => 1})->path_query());
-        return;
+        return redirect uri_for('/', {nosuchdevice => 1})->path_query;
     }
 
     params->{'tab'} ||= 'details';
diff --git a/Netdisco/lib/App/Netdisco/Web/Plugin.pm b/Netdisco/lib/App/Netdisco/Web/Plugin.pm
index 37b147c8..29dc5ba2 100644
--- a/Netdisco/lib/App/Netdisco/Web/Plugin.pm
+++ b/Netdisco/lib/App/Netdisco/Web/Plugin.pm
@@ -23,8 +23,7 @@ register 'register_template_path' => sub {
   my ($self, $path) = plugin_args(@_);
 
   if (!length $path) {
-      error "bad template path to register_template_paths";
-      return;
+      return error "bad template path to register_template_paths";
   }
 
   unshift
@@ -36,13 +35,11 @@ sub _register_include {
   my ($type, $plugin) = @_;
 
   if (!length $type) {
-      error "bad type to _register_include";
-      return;
+      return error "bad type to _register_include";
   }
 
   if (!length $plugin) {
-      error "bad plugin name to register_$type";
-      return;
+      return error "bad plugin name to register_$type";
   }
 
   push @{ setting("_additional_$type") }, $plugin;
@@ -64,8 +61,7 @@ register 'register_device_port_column' => sub {
   $config->{position} ||= 'right';
 
   if (!length $config->{name} or !length $config->{label}) {
-      error "bad config to register_device_port_column";
-      return;
+      return error "bad config to register_device_port_column";
   }
 
   foreach my $item (@{ setting('_extra_device_port_cols') }) {
@@ -85,8 +81,7 @@ register 'register_navbar_item' => sub {
       or !length $config->{path}
       or !length $config->{label}) {
 
-      error "bad config to register_navbar_item";
-      return;
+      return error "bad config to register_navbar_item";
   }
 
   foreach my $item (@{ setting('_navbar_items') }) {
@@ -105,8 +100,7 @@ register 'register_admin_task' => sub {
   if (!length $config->{tag}
       or !length $config->{label}) {
 
-      error "bad config to register_admin_task";
-      return;
+      return error "bad config to register_admin_task";
   }
 
   setting('_admin_tasks')->{ $config->{tag} } = $config;
@@ -119,8 +113,7 @@ sub _register_tab {
   if (!length $config->{tag}
       or !length $config->{label}) {
 
-      error "bad config to register_${nav}_item";
-      return;
+      return error "bad config to register_${nav}_item";
   }
 
   foreach my $item (@{ $stash }) {
@@ -152,8 +145,7 @@ register 'register_report' => sub {
       or !length $config->{label}
       or 0 == scalar grep {$config->{category} eq $_} @categories) {
 
-      error "bad config to register_report";
-      return;
+      return error "bad config to register_report";
   }
 
   foreach my $item (@{setting('_reports_menu')->{ $config->{category} }}) {
diff --git a/Netdisco/lib/App/Netdisco/Web/Plugin/AdminTask/JobQueue.pm b/Netdisco/lib/App/Netdisco/Web/Plugin/AdminTask/JobQueue.pm
index 8a67a359..c932c55c 100644
--- a/Netdisco/lib/App/Netdisco/Web/Plugin/AdminTask/JobQueue.pm
+++ b/Netdisco/lib/App/Netdisco/Web/Plugin/AdminTask/JobQueue.pm
@@ -12,8 +12,8 @@ register_admin_task({
 });
 
 ajax '/ajax/control/admin/jobqueue/del' => sub {
-    return unless var('user') and var('user')->admin;
-    return unless length param('job');
+    send_error('Forbidden', 403) unless var('user')->admin;
+    send_error('Missing job', 400) unless length param('job');
 
     schema('netdisco')->txn_do(sub {
       my $device = schema('netdisco')->resultset('Admin')
@@ -22,7 +22,7 @@ ajax '/ajax/control/admin/jobqueue/del' => sub {
 };
 
 ajax '/ajax/content/admin/jobqueue' => sub {
-    return unless var('user') and var('user')->admin;
+    send_error('Forbidden', 403) unless var('user')->admin;
 
     my $set = schema('netdisco')->resultset('Admin')
       ->with_times
diff --git a/Netdisco/lib/App/Netdisco/Web/Plugin/AdminTask/PseudoDevice.pm b/Netdisco/lib/App/Netdisco/Web/Plugin/AdminTask/PseudoDevice.pm
index 64fe8b06..6a4d9300 100644
--- a/Netdisco/lib/App/Netdisco/Web/Plugin/AdminTask/PseudoDevice.pm
+++ b/Netdisco/lib/App/Netdisco/Web/Plugin/AdminTask/PseudoDevice.pm
@@ -29,7 +29,7 @@ sub _sanity_ok {
 }
 
 ajax '/ajax/control/admin/pseudodevice/add' => sub {
-    return unless _sanity_ok();
+    send_error('Bad Request', 400) unless _sanity_ok();
 
     schema('netdisco')->txn_do(sub {
       my $device = schema('netdisco')->resultset('Device')
@@ -49,7 +49,7 @@ ajax '/ajax/control/admin/pseudodevice/add' => sub {
 };
 
 ajax '/ajax/control/admin/pseudodevice/del' => sub {
-    return unless _sanity_ok();
+    send_error('Bad Request', 400) unless _sanity_ok();
 
     schema('netdisco')->txn_do(sub {
       my $device = schema('netdisco')->resultset('Device')
@@ -61,7 +61,7 @@ ajax '/ajax/control/admin/pseudodevice/del' => sub {
 };
 
 ajax '/ajax/control/admin/pseudodevice/update' => sub {
-    return unless _sanity_ok();
+    send_error('Bad Request', 400) unless _sanity_ok();
 
     schema('netdisco')->txn_do(sub {
       my $device = schema('netdisco')->resultset('Device')
@@ -86,7 +86,7 @@ ajax '/ajax/control/admin/pseudodevice/update' => sub {
 };
 
 ajax '/ajax/content/admin/pseudodevice' => sub {
-    return unless var('user') and var('user')->admin;
+    send_error('Forbidden', 403) unless var('user')->admin;
 
     my $set = schema('netdisco')->resultset('Device')
       ->search(
diff --git a/Netdisco/lib/App/Netdisco/Web/Plugin/AdminTask/Topology.pm b/Netdisco/lib/App/Netdisco/Web/Plugin/AdminTask/Topology.pm
index 97284f65..c0dbd2ac 100644
--- a/Netdisco/lib/App/Netdisco/Web/Plugin/AdminTask/Topology.pm
+++ b/Netdisco/lib/App/Netdisco/Web/Plugin/AdminTask/Topology.pm
@@ -28,7 +28,7 @@ sub _sanity_ok {
 }
 
 ajax '/ajax/control/admin/topology/add' => sub {
-    return unless _sanity_ok();
+    send_error('Bad Request', 400) unless _sanity_ok();
 
     my $device = schema('netdisco')->resultset('Topology')
       ->create({
@@ -75,7 +75,7 @@ ajax '/ajax/control/admin/topology/add' => sub {
 };
 
 ajax '/ajax/control/admin/topology/del' => sub {
-    return unless _sanity_ok();
+    send_error('Bad Request', 400) unless _sanity_ok();
 
     schema('netdisco')->txn_do(sub {
       my $device = schema('netdisco')->resultset('Topology')
@@ -89,7 +89,7 @@ ajax '/ajax/control/admin/topology/del' => sub {
 };
 
 ajax '/ajax/content/admin/topology' => sub {
-    return unless var('user') and var('user')->admin;
+    send_error('Forbidden', 403) unless var('user')->admin;
 
     my $set = schema('netdisco')->resultset('Topology')
       ->search({},{order_by => [qw/dev1 dev2 port1/]});
diff --git a/Netdisco/lib/App/Netdisco/Web/Plugin/Device/Addresses.pm b/Netdisco/lib/App/Netdisco/Web/Plugin/Device/Addresses.pm
index ad55025b..66013836 100644
--- a/Netdisco/lib/App/Netdisco/Web/Plugin/Device/Addresses.pm
+++ b/Netdisco/lib/App/Netdisco/Web/Plugin/Device/Addresses.pm
@@ -13,7 +13,7 @@ ajax '/ajax/content/device/addresses' => sub {
     my $q = param('q');
 
     my $device = schema('netdisco')->resultset('Device')
-      ->search_for_device($q) or return;
+      ->search_for_device($q) or send_error('Bad device', 400);
 
     my $set = $device->device_ips->search({}, {order_by => 'alias'});
     return unless $set->count;
diff --git a/Netdisco/lib/App/Netdisco/Web/Plugin/Device/Details.pm b/Netdisco/lib/App/Netdisco/Web/Plugin/Device/Details.pm
index 6e6d30a4..e40113fb 100644
--- a/Netdisco/lib/App/Netdisco/Web/Plugin/Device/Details.pm
+++ b/Netdisco/lib/App/Netdisco/Web/Plugin/Device/Details.pm
@@ -12,7 +12,7 @@ register_device_tab({ tag => 'details', label => 'Details' });
 ajax '/ajax/content/device/details' => sub {
     my $q = param('q');
     my $device = schema('netdisco')->resultset('Device')
-      ->with_times()->search_for_device($q) or return;
+      ->with_times()->search_for_device($q) or send_error('Bad device', 400);
 
     content_type('text/html');
     template 'ajax/device/details.tt', {
diff --git a/Netdisco/lib/App/Netdisco/Web/Plugin/Device/Neighbors.pm b/Netdisco/lib/App/Netdisco/Web/Plugin/Device/Neighbors.pm
index 106919e8..e43fb1da 100644
--- a/Netdisco/lib/App/Netdisco/Web/Plugin/Device/Neighbors.pm
+++ b/Netdisco/lib/App/Netdisco/Web/Plugin/Device/Neighbors.pm
@@ -43,7 +43,7 @@ get '/ajax/data/device/netmap' => sub {
     my $q = param('q');
 
     my $device = schema('netdisco')->resultset('Device')
-      ->search_for_device($q) or return;
+      ->search_for_device($q) or send_error('Bad device', 400);
     my $start = $device->ip;
 
     my @devices = schema('netdisco')->resultset('Device')->search({}, {
@@ -72,7 +72,7 @@ get '/ajax/data/device/netmap' => sub {
     _add_children($tree{children}, var('links')->{$start});
 
     content_type('application/json');
-    return to_json(\%tree);
+    to_json(\%tree);
 };
 
 ajax '/ajax/data/device/alldevicelinks' => sub {
@@ -93,7 +93,7 @@ ajax '/ajax/data/device/alldevicelinks' => sub {
     }
 
     content_type('application/json');
-    return to_json(\%tree);
+    to_json(\%tree);
 };
 
 true;
diff --git a/Netdisco/lib/App/Netdisco/Web/Plugin/Device/Ports.pm b/Netdisco/lib/App/Netdisco/Web/Plugin/Device/Ports.pm
index 12ac58a7..6163b941 100644
--- a/Netdisco/lib/App/Netdisco/Web/Plugin/Device/Ports.pm
+++ b/Netdisco/lib/App/Netdisco/Web/Plugin/Device/Ports.pm
@@ -14,7 +14,7 @@ ajax '/ajax/content/device/ports' => sub {
     my $q = param('q');
 
     my $device = schema('netdisco')->resultset('Device')
-      ->search_for_device($q) or return;
+      ->search_for_device($q) or send_error('Bad device', 400);
     my $set = $device->ports;
 
     # refine by ports if requested
diff --git a/Netdisco/lib/App/Netdisco/Web/Plugin/Search/Device.pm b/Netdisco/lib/App/Netdisco/Web/Plugin/Search/Device.pm
index 47cfdae4..58c933a1 100644
--- a/Netdisco/lib/App/Netdisco/Web/Plugin/Search/Device.pm
+++ b/Netdisco/lib/App/Netdisco/Web/Plugin/Search/Device.pm
@@ -21,7 +21,7 @@ ajax '/ajax/content/search/device' => sub {
     }
     else {
         my $q = param('q');
-        return unless $q;
+        send_error('Missing query', 400) unless $q;
 
         $set = schema('netdisco')->resultset('Device')->search_fuzzy($q);
     }
diff --git a/Netdisco/lib/App/Netdisco/Web/Plugin/Search/Node.pm b/Netdisco/lib/App/Netdisco/Web/Plugin/Search/Node.pm
index beaec028..ace6ecbb 100644
--- a/Netdisco/lib/App/Netdisco/Web/Plugin/Search/Node.pm
+++ b/Netdisco/lib/App/Netdisco/Web/Plugin/Search/Node.pm
@@ -14,7 +14,7 @@ register_search_tab({ tag => 'node', label => 'Node' });
 # nodes matching the param as an IP or DNS hostname or MAC
 ajax '/ajax/content/search/node' => sub {
     my $node = param('q');
-    return unless $node;
+    send_error('Missing node', 400) unless $node;
     content_type('text/html');
 
     my $mac = Net::MAC->new(mac => $node, 'die' => 0, verbose => 0);
diff --git a/Netdisco/lib/App/Netdisco/Web/Plugin/Search/Port.pm b/Netdisco/lib/App/Netdisco/Web/Plugin/Search/Port.pm
index 047ce6ce..2415d359 100644
--- a/Netdisco/lib/App/Netdisco/Web/Plugin/Search/Port.pm
+++ b/Netdisco/lib/App/Netdisco/Web/Plugin/Search/Port.pm
@@ -11,7 +11,7 @@ register_search_tab({ tag => 'port', label => 'Port' });
 # device ports with a description (er, name) matching
 ajax '/ajax/content/search/port' => sub {
     my $q = param('q');
-    return unless $q;
+    send_error('Missing query', 400) unless $q;
     my $set;
 
     if ($q =~ m/^\d+$/) {
diff --git a/Netdisco/lib/App/Netdisco/Web/Plugin/Search/VLAN.pm b/Netdisco/lib/App/Netdisco/Web/Plugin/Search/VLAN.pm
index 46b8ba44..f204c4e5 100644
--- a/Netdisco/lib/App/Netdisco/Web/Plugin/Search/VLAN.pm
+++ b/Netdisco/lib/App/Netdisco/Web/Plugin/Search/VLAN.pm
@@ -11,7 +11,7 @@ register_search_tab({ tag => 'vlan', label => 'VLAN' });
 # devices carrying vlan xxx
 ajax '/ajax/content/search/vlan' => sub {
     my $q = param('q');
-    return unless $q;
+    send_error('Missing query', 400) unless $q;
     my $set;
 
     if ($q =~ m/^\d+$/) {
diff --git a/Netdisco/lib/App/Netdisco/Web/PortControl.pm b/Netdisco/lib/App/Netdisco/Web/PortControl.pm
index 604bb935..d2defc0a 100644
--- a/Netdisco/lib/App/Netdisco/Web/PortControl.pm
+++ b/Netdisco/lib/App/Netdisco/Web/PortControl.pm
@@ -5,8 +5,10 @@ use Dancer::Plugin::Ajax;
 use Dancer::Plugin::DBIC;
 
 ajax '/ajax/portcontrol' => sub {
-    return unless var('user')->port_control;
-    return unless param('device') and param('port') and param('field');
+    send_error('Forbidden', 403)
+      unless var('user')->port_control;
+    send_error('No device/port/field', 400)
+      unless param('device') and param('port') and param('field');
 
     my $log = sprintf 'd:[%s] p:[%s] f:[%s]. a:[%s] v[%s]',
       param('device'), (param('port') || ''), param('field'),
@@ -21,7 +23,8 @@ ajax '/ajax/portcontrol' => sub {
       'c_power'  => 'power',
     );
 
-    return unless (param('action') or param('value'));
+    send_error('No action/value', 400)
+      unless (param('action') or param('value'));
 
     my $action = $action_map{ param('field') };
     my $subaction = ($action =~ m/^(?:power|portcontrol)/
@@ -45,7 +48,7 @@ ajax '/ajax/portcontrol' => sub {
 
 ajax '/ajax/userlog' => sub {
     my $user = session('user');
-    send_error('No username') unless $user;
+    send_error('No username', 400) unless $user;
 
     my $rs = schema('netdisco')->resultset('Admin')->search({
       username => $user,
diff --git a/Netdisco/lib/App/Netdisco/Web/Search.pm b/Netdisco/lib/App/Netdisco/Web/Search.pm
index 939e071b..b623ab0c 100644
--- a/Netdisco/lib/App/Netdisco/Web/Search.pm
+++ b/Netdisco/lib/App/Netdisco/Web/Search.pm
@@ -65,9 +65,7 @@ get '/search' => sub {
 
     if (not param('tab')) {
         if (not $q) {
-            status(302);
-            header(Location => uri_for('/')->path_query());
-            return;
+            return redirect uri_for('/')->path_query;
         }
 
         # pick most likely tab for initial results
@@ -80,13 +78,11 @@ get '/search' => sub {
             if ($nd and $nd->count) {
                 if ($nd->count == 1) {
                     # redirect to device details for the one device
-                    status(302);
-                    header(Location => uri_for('/device', {
+                    return redirect uri_for('/device', {
                       tab => 'details',
                       q => ($nd->first->dns || $nd->first->ip),
                       f => '',
-                    })->path_query());
-                    return;
+                    })->path_query;
                 }
 
                 # multiple devices
diff --git a/Netdisco/lib/App/Netdisco/Web/TypeAhead.pm b/Netdisco/lib/App/Netdisco/Web/TypeAhead.pm
index 6ccd37f8..38033796 100644
--- a/Netdisco/lib/App/Netdisco/Web/TypeAhead.pm
+++ b/Netdisco/lib/App/Netdisco/Web/TypeAhead.pm
@@ -11,7 +11,7 @@ ajax '/ajax/data/devicename/typeahead' => sub {
     my $set = schema('netdisco')->resultset('Device')->search_fuzzy($q);
 
     content_type 'application/json';
-    return to_json [map {$_->dns || $_->name || $_->ip} $set->all];
+    to_json [map {$_->dns || $_->name || $_->ip} $set->all];
 };
 
 ajax '/ajax/data/deviceip/typeahead' => sub {
@@ -29,27 +29,26 @@ ajax '/ajax/data/deviceip/typeahead' => sub {
     }
 
     content_type 'application/json';
-    return to_json \@data;
+    to_json \@data;
 };
 
 ajax '/ajax/data/port/typeahead' => sub {
     my $dev  = param('dev1')  || param('dev2');
     my $port = param('port1') || param('port2');
-    return unless length $dev;
+    send_error('Missing device', 400) unless length $dev;
 
     my $device = schema('netdisco')->resultset('Device')
       ->find({ip => $dev});
-    return unless $device;
+    send_error('Bad device', 400) unless $device;
 
     my $set = $device->ports({},{order_by => 'port'});
     $set = $set->search({port => { -ilike => "\%$port\%" }})
       if length $port;
 
     my $results = [ sort { &App::Netdisco::Util::Web::sort_port($a->port, $b->port) } $set->all ];
-    return unless scalar @$results;
 
     content_type 'application/json';
-    return to_json [map {$_->port} @$results];
+    to_json [map {$_->port} @$results];
 };
 
 true;