diff --git a/code/app/Circle.php b/code/app/Circle.php
new file mode 100644
index 00000000..a5886cf0
--- /dev/null
+++ b/code/app/Circle.php
@@ -0,0 +1,33 @@
+<?php
+
+namespace App;
+
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+
+use App\Models\Concerns\TracksUpdater;
+use App\Models\Concerns\ModifiableTrait;
+use App\Events\SluggableCreating;
+
+class Circle extends Model
+{
+    use GASModel, SluggableID, TracksUpdater, ModifiableTrait;
+
+    public $incrementing = false;
+    protected $keyType = 'string';
+
+    protected $dispatchesEvents = [
+        'creating' => SluggableCreating::class
+    ];
+
+    protected static function boot()
+    {
+        parent::boot();
+        static::initTrackingEvents();
+    }
+
+    public function group(): BelongsTo
+    {
+        return $this->belongsTo(Group::class);
+    }
+}
diff --git a/code/app/Observers/UserObserver.php b/code/app/Observers/UserObserver.php
index e23e55c0..1215eb71 100644
--- a/code/app/Observers/UserObserver.php
+++ b/code/app/Observers/UserObserver.php
@@ -68,7 +68,7 @@ private function createdNormal($user)
         foreach($groups as $group) {
             $circle = $group->circles()->where('is_default', true)->first();
             if ($circle) {
-                $circles[] = $circle;
+                $circles[] = $circle->id;
             }
         }
 
diff --git a/code/app/Providers/ServicesProvider.php b/code/app/Providers/ServicesProvider.php
index 96c91307..bc2f29db 100644
--- a/code/app/Providers/ServicesProvider.php
+++ b/code/app/Providers/ServicesProvider.php
@@ -20,9 +20,11 @@ private function services(): array
         */
         return [
             \App\Services\BookingsService::class,
+            \App\Services\CirclesService::class,
             \App\Services\DatesService::class,
             \App\Services\DynamicBookingsService::class,
             \App\Services\FastBookingsService::class,
+            \App\Services\GroupsService::class,
             \App\Services\InvoicesService::class,
             \App\Services\ModifiersService::class,
             \App\Services\ModifierTypesService::class,
diff --git a/code/app/Services/BookingsService.php b/code/app/Services/BookingsService.php
index f1b164a7..add571b7 100644
--- a/code/app/Services/BookingsService.php
+++ b/code/app/Services/BookingsService.php
@@ -396,7 +396,7 @@ public function handleBookingUpdate($request, $user, $order, $target_user, $deli
         $booking = $this->readBooking($request, $order, $booking, $delivering);
 
         if ($booking) {
-            $booking->circles()->sync($request['circles']);
+            $booking->circles()->sync($request['circles'] ?? []);
 
             if ($delivering) {
                 BookingDelivered::dispatch($booking, $request['action'], $user);
diff --git a/code/app/Services/CirclesService.php b/code/app/Services/CirclesService.php
index ae645879..4c1de380 100644
--- a/code/app/Services/CirclesService.php
+++ b/code/app/Services/CirclesService.php
@@ -4,6 +4,7 @@
 
 use Illuminate\Support\Facades\DB;
 
+use App\User;
 use App\Circle;
 use App\Group;
 
@@ -29,10 +30,22 @@ public function store(array $request)
 
         if ($group->circles()->count() == 0) {
             $c->is_default = true;
+            $was_first = true;
+        }
+        else {
+            $was_first = false;
         }
 
         $c->save();
 
+        if ($was_first) {
+            if ($group->context == 'user') {
+                foreach(User::all() as $user) {
+                    $user->circles()->attach($c->id);
+                }
+            }
+        }
+
         return $c;
     }
 
@@ -67,6 +80,14 @@ public function destroy($id)
                 $new_default = $other->first();
                 $new_default->is_default = true;
                 $new_default->save();
+
+                $users = User::whereHas('circles', function($query) use ($c) {
+                    $query->where('circles.id', $c->id);
+                })->get();
+
+                foreach($users as $user) {
+                    $user->circles()->attach($new_default->id);
+                }
             }
         }
 
diff --git a/code/app/Services/GroupsService.php b/code/app/Services/GroupsService.php
index 27ce4d6d..705cff60 100644
--- a/code/app/Services/GroupsService.php
+++ b/code/app/Services/GroupsService.php
@@ -31,10 +31,9 @@ public function update($id, array $request)
 
         $g = Group::findOrFail($id);
         $this->setIfSet($g, $request, 'name');
-        $this->setIfSet($g, $request, 'context');
+        $this->setIfSet($g, $request, 'context', 'user');
 
-        $context = $request['context'] ?? 'user';
-        switch($context) {
+        switch($g->context) {
             case 'user':
                 $this->setIfSet($g, $request, 'cardinality');
                 $this->boolIfSet($g, $request, 'filters_orders');
diff --git a/code/tests/Features/AggregationsTest.php b/code/tests/Features/AggregationsTest.php
new file mode 100644
index 00000000..f0033949
--- /dev/null
+++ b/code/tests/Features/AggregationsTest.php
@@ -0,0 +1,244 @@
+<?php
+
+namespace Tests\Services;
+
+use Tests\TestCase;
+use Illuminate\Foundation\Testing\DatabaseTransactions;
+
+class AggregationsTest extends TestCase
+{
+    use DatabaseTransactions;
+
+    private function createBasicGroup($params)
+    {
+        $this->actingAs($this->userAdmin);
+
+        $groups_service = app()->make('GroupsService');
+        $circles_service = app()->make('CirclesService');
+
+        $group = $groups_service->store(['name' => 'Gruppo Test']);
+        $groups_service->update($group->id, array_merge(['name' => 'Gruppo Test'], $params));
+
+        $this->nextRound();
+
+        $circles_service->store([
+            'name' => 'Cerchio Test 1',
+            'group_id' => $group->id,
+        ]);
+
+        $this->nextRound();
+
+        $circles_service->store([
+            'name' => 'Cerchio Test 2',
+            'group_id' => $group->id,
+        ]);
+
+        $this->nextRound();
+
+        return $group;
+    }
+
+    public function testCreate()
+    {
+        $group = $this->createBasicGroup([
+            'context' => 'user',
+            'cardinality' => 'single',
+            'filters_orders' => true,
+        ]);
+
+        $this->assertFalse(is_null($group));
+        $this->assertEquals('Gruppo Test', $group->name);
+        $this->assertEquals(2, $group->circles()->count());
+        $this->assertEquals(1, $this->userAdmin->circles()->count());
+    }
+
+    private function attachModifier($circle, $amount)
+    {
+        $this->actingAs($this->userAdmin);
+
+        app()->make('ModifierTypesService')->update('spese-trasporto', [
+            'classes' => ['App\Booking', 'App\Product', 'App\Circle'],
+        ]);
+
+        $this->nextRound();
+
+        $test_shipping_value = 10;
+        $modifiers = $circle->applicableModificationTypes();
+        $modifier = null;
+
+        foreach ($modifiers as $mod) {
+            if ($mod->id == 'spese-trasporto') {
+                $mod = $circle->modifiers()->where('modifier_type_id', $mod->id)->first();
+                app()->make('ModifiersService')->update($mod->id, [
+                    'value' => 'absolute',
+                    'arithmetic' => 'sum',
+                    'scale' => 'minor',
+                    'applies_type' => 'none',
+                    'applies_target' => 'booking',
+                    'distribution_type' => 'none',
+                    'simplified_amount' => $test_shipping_value,
+                ]);
+
+                $modifier = $mod;
+                break;
+            }
+        }
+
+        $this->assertNotNull($modifier);
+
+        $this->nextRound();
+        return $modifier;
+    }
+
+    public function testUserModifiers()
+    {
+        $group = $this->createBasicGroup([
+            'context' => 'user',
+            'cardinality' => 'single',
+            'filters_orders' => false,
+        ]);
+
+        $right_circle = $group->circles()->where('is_default', false)->first();
+        $wrong_circle = $group->circles()->where('circles.id', '!=', $right_circle->id)->first();
+
+        $order = $this->initOrder(null);
+        $this->populateOrder($order);
+
+        $this->nextRound();
+
+        $target_user = $this->users->first();
+        $target_user->circles()->sync([$right_circle->id]);
+
+        $test_shipping_value = 10;
+        $mod = $this->attachModifier($right_circle, $test_shipping_value);
+
+        $order = app()->make('OrdersService')->show($order->id);
+        $redux = $order->aggregate->reduxData();
+        $this->assertNotEquals($redux->price, 0.0);
+        $checked = false;
+
+        foreach($order->bookings as $booking) {
+            $mods = $booking->applyModifiers($redux, true);
+
+            if ($booking->user->id != $target_user->id) {
+                $this->assertEquals($mods->count(), 0);
+            }
+            else {
+                $this->assertEquals($mods->count(), 1);
+
+                foreach($mods as $m) {
+                    $this->assertEquals($m->effective_amount, $test_shipping_value);
+                    $this->assertEquals($m->modifier_id, $mod->id);
+                }
+
+                $checked = true;
+            }
+        }
+
+        $this->assertTrue($checked);
+    }
+
+    public function testBookingModifiers()
+    {
+        $group = $this->createBasicGroup([
+            'context' => 'booking',
+        ]);
+
+        $right_circle = $group->circles()->where('is_default', false)->first();
+        $wrong_circle = $group->circles()->where('circles.id', '!=', $right_circle->id)->first();
+
+        $order = $this->initOrder(null);
+        $this->populateOrder($order);
+
+        $this->nextRound();
+
+        $order = app()->make('OrdersService')->show($order->id);
+
+        do {
+            $target_bookings = [];
+
+            foreach($order->bookings as $booking) {
+                if (rand() % 2 == 0) {
+                    $booking->circles()->sync([$right_circle->id]);
+                    $target_bookings[] = $booking->id;
+                }
+                else {
+                    $booking->circles()->sync([$wrong_circle->id]);
+                }
+            }
+        } while(empty($target_bookings) && count($target_bookings) != $order->bookings->count());
+
+        $test_shipping_value = 10;
+        $mod = $this->attachModifier($right_circle, $test_shipping_value);
+
+        $order = app()->make('OrdersService')->show($order->id);
+        $redux = $order->aggregate->reduxData();
+        $this->assertNotEquals($redux->price, 0.0);
+        $checked = false;
+
+        foreach($order->bookings as $booking) {
+            $mods = $booking->applyModifiers($redux, true);
+
+            if (in_array($booking->id, $target_bookings) == false) {
+                $this->assertEquals($mods->count(), 0);
+            }
+            else {
+                $this->assertEquals($mods->count(), 1);
+
+                foreach($mods as $m) {
+                    $this->assertEquals($m->effective_amount, $test_shipping_value);
+                    $this->assertEquals($m->modifier_id, $mod->id);
+                }
+
+                $checked = true;
+            }
+        }
+
+        $this->assertTrue($checked);
+    }
+
+    public function testAssociateOrder()
+    {
+        $group = $this->createBasicGroup([
+            'context' => 'user',
+            'cardinality' => 'single',
+            'filters_orders' => true,
+        ]);
+
+        $right_circle = $group->circles()->first();
+        $wrong_circle = $group->circles()->where('circles.id', '!=', $right_circle->id)->first();
+
+        $order = $this->initOrder(null);
+
+        $this->actingAs($this->userReferrer);
+        app()->make('OrdersService')->update($order->id, [
+            'circles' => [$right_circle->id],
+        ]);
+
+        $this->nextRound();
+
+        $order = app()->make('OrdersService')->show($order->id);
+        $this->assertEquals(1, $order->circles()->count());
+        $this->assertEquals($right_circle->id, $order->circles()->first()->id);
+
+        $this->nextRound();
+
+        $user_yes = $this->createRoleAndUser($this->gas, 'supplier.book');
+        $user_yes->circles()->sync([$right_circle->id]);
+
+        $user_no = $this->createRoleAndUser($this->gas, 'supplier.book');
+        $user_no->circles()->sync([$wrong_circle->id]);
+
+        $this->nextRound();
+
+        $this->actingAs($user_yes);
+        $orders = getOrdersByStatus($user_yes, 'open');
+        $this->assertEquals(1, $orders->count());
+
+        $this->nextRound();
+
+        $this->actingAs($user_no);
+        $orders = getOrdersByStatus($user_no, 'open');
+        $this->assertEquals(0, $orders->count());
+    }
+}
diff --git a/code/tests/Services/ModifierTypesServiceTest.php b/code/tests/Services/ModifierTypesServiceTest.php
index d19fc7be..9184aa27 100644
--- a/code/tests/Services/ModifierTypesServiceTest.php
+++ b/code/tests/Services/ModifierTypesServiceTest.php
@@ -33,10 +33,10 @@ public function testStore()
     {
         $this->actingAs($this->userWithAdminPerm);
 
-        $type = app()->make('ModifierTypesService')->store(array(
+        $type = app()->make('ModifierTypesService')->store([
             'name' => 'Donazione',
             'classes' => ['App\Booking'],
-        ));
+        ]);
 
         $this->assertTrue($type->exists);
 
diff --git a/code/tests/Services/ModifiersServiceTest.php b/code/tests/Services/ModifiersServiceTest.php
index 4c3a3594..9c39dd6c 100644
--- a/code/tests/Services/ModifiersServiceTest.php
+++ b/code/tests/Services/ModifiersServiceTest.php
@@ -13,11 +13,6 @@ class ModifiersServiceTest extends TestCase
 {
     use DatabaseTransactions;
 
-    public function setUp(): void
-    {
-        parent::setUp();
-    }
-
     private function localInitOrder()
     {
         $this->order = $this->initOrder(null);
@@ -678,56 +673,6 @@ public function testOnBooking()
         }
     }
 
-    /*
-        Modificatore applicato su Luogo di Consegna
-    */
-    public function testOnShippingPlace()
-    {
-        $this->localInitOrder();
-        $this->actingAs($this->userAdmin);
-
-        $delivery_1 = \App\Delivery::factory()->create([
-            'default' => true,
-        ]);
-
-        $delivery_2 = \App\Delivery::factory()->create([
-            'default' => false,
-        ]);
-
-        $delivery = [$delivery_1, $delivery_2];
-
-        foreach($this->users as $user) {
-            $user->preferred_delivery_id = $delivery[rand(0, 1)]->id;
-            $user->save();
-        }
-
-        $test_shipping_value = 10;
-        $mod = $this->simpleMod($delivery_2, 'booking', 'none', $test_shipping_value);
-        $this->assertNotNull($mod);
-
-        $this->nextRound();
-
-        $order = app()->make('OrdersService')->show($this->order->id);
-        $redux = $order->aggregate->reduxData();
-        $this->assertNotEquals($redux->price, 0.0);
-
-        foreach($order->bookings as $booking) {
-            $mods = $booking->applyModifiers($redux, true);
-
-            if ($booking->user->preferred_delivery_id == $delivery_1->id) {
-                $this->assertEquals($mods->count(), 0);
-            }
-            else {
-                $this->assertEquals($mods->count(), 1);
-
-                foreach($mods as $m) {
-                    $this->assertEquals($m->effective_amount, $test_shipping_value);
-                    $this->assertEquals($m->modifier_id, $mod->id);
-                }
-            }
-        }
-    }
-
     private function pushFriend($master)
     {
         $friends_role = \App\Role::factory()->create(['actions' => 'users.subusers']);
@@ -851,7 +796,7 @@ public function testWithFriend()
         $shipping_cost_found = false;
 
         $printer = new OrderPrinter();
-        $formatted = $printer->formatShipping($order, splitFields(['lastname', 'firstname', 'name', 'quantity', 'price']), 'booked', 'all_by_name', 1);
+        $formatted = $printer->formatShipping($order, splitFields(['lastname', 'firstname', 'name', 'quantity', 'price']), 'booked', ['all_by_name'], 1);
 
         foreach($formatted->contents as $d) {
             if ($d->user_id == $booking->user_id) {
@@ -911,7 +856,7 @@ public function testWithOnlyFriend()
         $shipping_cost_found = false;
 
         $printer = new OrderPrinter();
-        $formatted = $printer->formatShipping($order, splitFields(['lastname', 'firstname', 'name', 'quantity', 'price']), 'booked', 'all_by_name', 1);
+        $formatted = $printer->formatShipping($order, splitFields(['lastname', 'firstname', 'name', 'quantity', 'price']), 'booked', ['all_by_name'], 1);
 
         foreach($formatted->contents as $d) {
             if ($d->user_id == $newUser->id) {
diff --git a/code/tests/Services/OrdersServiceTest.php b/code/tests/Services/OrdersServiceTest.php
index 4a80ddb7..baa06ac5 100644
--- a/code/tests/Services/OrdersServiceTest.php
+++ b/code/tests/Services/OrdersServiceTest.php
@@ -12,7 +12,6 @@
 use App\Exceptions\AuthException;
 
 use App\User;
-use App\Delivery;
 use App\Booking;
 use App\VariantCombo;
 
@@ -178,33 +177,6 @@ public function testChangeState()
         $this->assertFalse($order->isRunning());
     }
 
-    /*
-        Assegnazione Luoghi di Consegna
-    */
-    public function testOnShippingPlace()
-    {
-        $this->actingAs($this->userAdmin);
-        $delivery = Delivery::factory()->create([
-            'default' => true,
-        ]);
-
-        $this->actingAs($this->userReferrer);
-        app()->make('OrdersService')->update($this->order->id, array(
-            'deliveries' => [$delivery->id],
-        ));
-
-        $order = app()->make('OrdersService')->show($this->order->id);
-        $this->assertEquals(1, $order->deliveries()->count());
-
-        /*
-            TODO: spostare funzione list() in OrdersService e testare che
-            userWithNoPerms non veda l'ordine appena modificato
-
-            $this->userWithNoPerms->preferred_delivery_id = $delivery->id;
-            $this->actingAs($this->userWithNoPerms);
-        */
-    }
-
     /*
         Accesso Ordine con ID non esistente
     */
diff --git a/code/tests/Services/UsersServiceTest.php b/code/tests/Services/UsersServiceTest.php
index 67b280b8..656db4ad 100644
--- a/code/tests/Services/UsersServiceTest.php
+++ b/code/tests/Services/UsersServiceTest.php
@@ -6,6 +6,7 @@
 use Illuminate\Database\Eloquent\ModelNotFoundException;
 use Illuminate\Support\Facades\Auth;
 use Illuminate\Support\Facades\Hash;
+use Illuminate\Support\Str;
 
 use Tests\TestCase;
 use App\Exceptions\IllegalArgumentException;
@@ -359,6 +360,24 @@ public function testInvalidCardNumber()
         ]);
     }
 
+    /*
+        Modifica Utente con parametri errati
+    */
+    public function testInvalidName()
+    {
+        $this->expectException(IllegalArgumentException::class);
+
+        $this->actingAs($this->userWithAdminPerm);
+        $sample = User::where('gas_id', $this->gas->id)->inRandomOrder()->first();
+
+        app()->make('UsersService')->store([
+            'username' => Str::random(10),
+            'firstname' => $sample->firstname,
+            'lastname' => $sample->lastname,
+            'password' => Str::random(10),
+        ]);
+    }
+
     /*
         Modifica del proprio Utente con permessi sbagliati
     */
diff --git a/code/tests/TestCase.php b/code/tests/TestCase.php
index 88743c85..6a7640cf 100644
--- a/code/tests/TestCase.php
+++ b/code/tests/TestCase.php
@@ -13,7 +13,6 @@ abstract class TestCase extends BaseTestCase
     use CreatesApplication;
 
     protected $baseUrl = 'http://localhost';
-    protected $services = null;
 
     public function setUp(): void
     {
@@ -66,9 +65,12 @@ public function tearDown(): void
     */
     protected function createRoleAndUser($gas, $permissions, $target = null)
     {
-        $role = \App\Role::factory()->create([
-            'actions' => $permissions
-        ]);
+        $role = \App\Role::where('actions', $permissions)->first();
+        if (is_null($role)) {
+            $role = \App\Role::factory()->create([
+                'actions' => $permissions
+            ]);
+        }
 
         $user = \App\User::factory()->create(['gas_id' => $gas->id]);
         $user->addRole($role->id, $target ?: $gas);