diff --git a/src/app/DataMigrator/DAV.php b/src/app/DataMigrator/DAV.php
--- a/src/app/DataMigrator/DAV.php
+++ b/src/app/DataMigrator/DAV.php
@@ -67,13 +67,21 @@
      */
     public function createItem(Item $item): void
     {
-        if ($item->existing) {
-            $href = $item->existing;
+        $is_file = false;
+        $href = $item->existing ?: null;
+
+        if (strlen($item->content)) {
+            $content = $item->content;
         } else {
-            $href = $this->getFolderPath($item->folder) . '/' . pathinfo($item->filename, PATHINFO_BASENAME);
+            $content = $item->filename;
+            $is_file = true;
+        }
+
+        if (empty($href)) {
+            $href = $this->getFolderPath($item->folder) . '/' . basename($item->filename);
         }
 
-        $object = new DAVOpaque($item->filename, true);
+        $object = new DAVOpaque($content, $is_file);
         $object->href = $href;
 
         switch ($item->folder->type) {
@@ -139,15 +147,6 @@
      */
     public function fetchItem(Item $item): void
     {
-        // Save the item content to a file
-        $location = $item->folder->location;
-
-        if (!file_exists($location)) {
-            mkdir($location, 0740, true);
-        }
-
-        $location .= '/' . basename($item->id);
-
         $result = $this->client->getObjects(dirname($item->id), $this->type2DAV($item->folder->type), [$item->id]);
 
         if ($result === false) {
@@ -156,11 +155,21 @@
 
         // TODO: Do any content changes, e.g. organizer/attendee email migration
 
-        if (file_put_contents($location, (string) $result[0]) === false) {
-            throw new \Exception("Failed to write to {$location}");
-        }
+        $content = (string) $result[0];
+
+        if (strlen($content) > Engine::MAX_ITEM_SIZE) {
+            // Save the item content to a file
+            $location = $item->folder->tempFileLocation(basename($item->id));
+
+            if (file_put_contents($location, $content) === false) {
+                throw new \Exception("Failed to write to {$location}");
+            }
 
-        $item->filename = $location;
+            $item->filename = $location;
+        } else {
+            $item->content = $content;
+            $item->filename = basename($item->id);
+        }
     }
 
     /**
diff --git a/src/app/DataMigrator/EWS.php b/src/app/DataMigrator/EWS.php
--- a/src/app/DataMigrator/EWS.php
+++ b/src/app/DataMigrator/EWS.php
@@ -4,6 +4,7 @@
 
 use App\DataMigrator\Interface\Folder;
 use App\DataMigrator\Interface\Item;
+use App\DataMigrator\Interface\ItemSet;
 use garethp\ews\API;
 use garethp\ews\API\Type;
 use Illuminate\Support\Facades\Http;
@@ -13,6 +14,9 @@
  */
 class EWS implements Interface\ExporterInterface
 {
+    /** @const int Max number of items to migrate in one go */
+    protected const CHUNK_SIZE = 20;
+
     /** @var API EWS API object */
     public $api;
 
@@ -31,15 +35,16 @@
 
     /** @var array Interal folders to skip */
     protected $folder_exceptions = [
+        'AllCategorizedItems',
         'AllContacts',
+        'AllContactsExtended',
         'AllPersonMetadata',
         'AllTodoTasks',
         'Document Centric Conversations',
         'ExternalContacts',
-        'Favorites',
         'Flagged Emails',
+        'Folder Memberships',
         'GraphFilesAndWorkingSetSearchFolder',
-        'My Contacts',
         'MyContactsExtended',
         'Orion Notes',
         'Outbox',
@@ -48,16 +53,22 @@
         'RelevantContacts',
         'SharedFilesSearchFolder',
         'Sharing',
+        'SpoolsPresentSharedItemsSearchFolder',
+        'SpoolsSearchFolder',
         'To-Do Search',
         'UserCuratedContacts',
         'XrmActivityStreamSearch',
         'XrmCompanySearch',
         'XrmDealSearch',
         'XrmSearch',
-        'Folder Memberships',
-        // TODO: These are different depending on a user locale
+        // TODO: These are different depending on a user locale and it's not possible
+        // to switch to English other than changing the user locale in OWA/Exchange.
         'Calendar/United States holidays',
+        'Favorites',
+        'My Contacts',
         'Kalendarz/Polska — dni wolne od pracy', // pl
+        'Ulubione', // pl
+        'Moje kontakty', // pl
     ];
 
     /** @var array Map of EWS folder types to Kolab types */
@@ -214,9 +225,31 @@
      */
     public function getFolders($types = []): array
     {
-        // Get full folders hierarchy
+        if (empty($types)) {
+            $types = array_values($this->type_map);
+        }
+
+        // Create FolderClass filter
+        $search = new Type\OrType();
+        foreach ($types as $type) {
+            $type = array_search($type, $this->type_map);
+            $search->addContains(Type\Contains::buildFromArray([
+                'FieldURI' => [
+                    Type\FieldURI::buildFromArray(['FieldURI' => 'folder:FolderClass']),
+                ],
+                'Constant' => Type\ConstantValueType::buildFromArray([
+                    'Value' => $type,
+                ]),
+                'ContainmentComparison' => 'Exact',
+                'ContainmentMode' => 'FullString',
+            ]));
+        }
+
+        // Get full folders hierarchy (filtered by folder class)
+        // Use of the filter reduces the response size by excluding system folders
         $options = [
             'Traversal' => 'Deep',
+            'Restriction' => ['Or' => $search],
         ];
 
         $folders = $this->api->getChildrenFolders('root', $options);
@@ -232,7 +265,7 @@
                 continue;
             }
 
-            // Note: Folder names are localized
+            // Note: Folder names are localized, even INBOX
             $name = $fullname = $folder->getDisplayName();
             $id = $folder->getFolderId()->getId();
             $parentId = $folder->getParentFolderId()->getId();
@@ -308,7 +341,10 @@
             'ItemShape' => [
                 'BaseShape' => 'IdOnly',
                 'AdditionalProperties' => [
-                    'FieldURI' => ['FieldURI' => 'item:ItemClass'],
+                    'FieldURI' => [
+                        ['FieldURI' => 'item:ItemClass'],
+                        // ['FieldURI' => 'item:Size'],
+                    ],
                 ],
             ],
         ];
@@ -325,10 +361,16 @@
         // Request first page
         $response = $this->api->getClient()->FindItem($request);
 
+        $set = new ItemSet();
+
         // @phpstan-ignore-next-line
-        foreach ($response as $item) {
+        foreach ($response->getItems() as $item) {
             if ($item = $this->toItem($item, $folder, $existing, $existingIndex)) {
-                $callback($item);
+                $set->items[] = $item;
+                if (count($set->items) == self::CHUNK_SIZE) {
+                    $callback($set);
+                    $set = new ItemSet();
+                }
             }
         }
 
@@ -337,13 +379,21 @@
             // @phpstan-ignore-next-line
             $response = $this->api->getNextPage($response);
 
-            foreach ($response as $item) {
+            foreach ($response->getItems() as $item) {
                 if ($item = $this->toItem($item, $folder, $existing, $existingIndex)) {
-                    $callback($item);
+                    $set->items[] = $item;
+                    if (count($set->items) == self::CHUNK_SIZE) {
+                        $callback($set);
+                        $set = new ItemSet();
+                    }
                 }
             }
         }
 
+        if (count($set->items)) {
+            $callback($set);
+        }
+
         // TODO: Delete items that do not exist anymore?
     }
 
@@ -356,12 +406,11 @@
         $this->initEnv($this->engine->queue);
 
         if ($driver = EWS\Item::factory($this, $item)) {
-            $item->filename = $driver->fetchItem($item);
+            $driver->processItem($item);
+            return;
         }
 
-        if (empty($item->filename)) {
-            throw new \Exception("Failed to fetch an item from EWS");
-        }
+        throw new \Exception("Failed to fetch an item from EWS");
     }
 
     /**
@@ -399,20 +448,16 @@
             $exists = $existing[$idx]['href'];
         }
 
-        $item = Item::fromArray([
-            'id' => $id,
+        if (!EWS\Item::isValidItem($item)) {
+            return null;
+        }
+
+        return Item::fromArray([
+            'id' => $id['Id'],
             'class' => $item->getItemClass(),
             'folder' => $folder,
             'existing' => $exists,
         ]);
-
-        // TODO: We don't need to instantiate Item at this point, instead
-        // implement EWS\Item::validateClass() method
-        if ($driver = EWS\Item::factory($this, $item)) {
-            return $item;
-        }
-
-        return null;
     }
 
     /**
diff --git a/src/app/DataMigrator/EWS/Appointment.php b/src/app/DataMigrator/EWS/Appointment.php
--- a/src/app/DataMigrator/EWS/Appointment.php
+++ b/src/app/DataMigrator/EWS/Appointment.php
@@ -18,7 +18,7 @@
     /**
      * Get GetItem request parameters
      */
-    protected function getItemRequest(): array
+    protected static function getItemRequest(): array
     {
         $request = parent::getItemRequest();
 
@@ -26,8 +26,7 @@
         $request['ItemShape']['IncludeMimeContent'] = true;
 
         // Get UID property, it's not included in the Default set
-        // FIXME: How to add the property to the set, not replace the whole set
-        $request['ItemShape']['AdditionalProperties']['FieldURI'] = ['FieldURI' => 'calendar:UID'];
+        $request['ItemShape']['AdditionalProperties']['FieldURI'][] = ['FieldURI' => 'calendar:UID'];
 
         return $request;
     }
@@ -35,7 +34,7 @@
     /**
      * Process event object
      */
-    protected function processItem(Type $item)
+    protected function convertItem(Type $item)
     {
         // Initialize $this->itemId (for some unit tests)
         $this->getUID($item);
diff --git a/src/app/DataMigrator/EWS/Contact.php b/src/app/DataMigrator/EWS/Contact.php
--- a/src/app/DataMigrator/EWS/Contact.php
+++ b/src/app/DataMigrator/EWS/Contact.php
@@ -16,7 +16,7 @@
     /**
      * Get GetItem request parameters
      */
-    protected function getItemRequest(): array
+    protected static function getItemRequest(): array
     {
         $request = parent::getItemRequest();
 
@@ -29,7 +29,7 @@
     /**
      * Process contact object
      */
-    protected function processItem(Type $item)
+    protected function convertItem(Type $item)
     {
         // Decode MIME content
         $vcard = base64_decode((string) $item->getMimeContent());
@@ -56,7 +56,7 @@
             $vcard = str_replace($matches[1], "X-SPOUSE:{$spouse}", $vcard);
         }
 
-        // TODO: X-MS-ANNIVERSARY;VALUE=DATE:2020-11-12
+        // Anniversary: X-MS-ANNIVERSARY;VALUE=DATE:2020-11-12
         if (preg_match('/(X-MS-ANNIVERSARY[;:][^\r\n]+)/', $vcard, $matches)) {
             $date = preg_replace('/^[^:]+:/', '', $matches[1]);
             $vcard = str_replace($matches[1], "X-ANNIVERSARY:{$date}", $vcard);
diff --git a/src/app/DataMigrator/EWS/DistList.php b/src/app/DataMigrator/EWS/DistList.php
--- a/src/app/DataMigrator/EWS/DistList.php
+++ b/src/app/DataMigrator/EWS/DistList.php
@@ -13,10 +13,23 @@
     public const TYPE        = 'IPM.DistList';
     public const FILE_EXT    = 'vcf';
 
+    /**
+     * Get GetItem request parameters
+     */
+    protected static function getItemRequest(): array
+    {
+        $request = parent::getItemRequest();
+
+        // Get Body property, it's not included in the Default set
+        $request['ItemShape']['AdditionalProperties']['FieldURI'] = ['FieldURI' => 'item:Body'];
+
+        return $request;
+    }
+
     /**
      * Convert distribution list object to vCard
      */
-    protected function processItem(Type $item)
+    protected function convertItem(Type $item)
     {
         // Groups (Distribution Lists) are not exported in vCard format, they use eml
 
@@ -34,11 +47,6 @@
             $vcard .= $this->formatProp($key, $prop[0], isset($prop[1]) ? $prop[1] : []);
         }
 
-        // TODO: The group description property in Exchange is not available via EWS XML,
-        // at least not at outlook.office.com (Exchange 2010). It is available in the
-        // MimeContent which is in email message format. However, Kolab Webclient does not
-        // make any use of the NOTE property for contact groups.
-
         // Process list members
         if ($members = $item->getMembers()) {
             // The Member property is either array (multiple members) or Type\MemberType
@@ -70,6 +78,11 @@
             }
         }
 
+        // Note: Kolab Webclient does not make any use of the NOTE property for contact groups
+        if ($body = (string) $item->getBody()) {
+            $vcard .= $this->formatProp('NOTE', $body);
+        }
+
         $vcard .= "END:VCARD\r\n";
 
         return $vcard;
diff --git a/src/app/DataMigrator/EWS/Item.php b/src/app/DataMigrator/EWS/Item.php
--- a/src/app/DataMigrator/EWS/Item.php
+++ b/src/app/DataMigrator/EWS/Item.php
@@ -3,8 +3,10 @@
 namespace App\DataMigrator\EWS;
 
 use App\DataMigrator\EWS;
+use App\DataMigrator\Engine;
 use App\DataMigrator\Interface\Folder as FolderInterface;
 use App\DataMigrator\Interface\Item as ItemInterface;
+use App\DataMigrator\Interface\ItemSet as ItemSetInterface;
 use garethp\ews\API;
 use garethp\ews\API\Type;
 
@@ -50,11 +52,24 @@
     }
 
     /**
-     * Fetch the specified object and put into a file
+     * Validate that specified EWS Item is of supported type
      */
-    public function fetchItem(ItemInterface $item)
+    public static function isValidItem(Type $item): bool
     {
-        $itemId = $item->id;
+        $item_class = str_replace('IPM.', '', $item->getItemClass());
+        $item_class = "\App\DataMigrator\EWS\\{$item_class}";
+
+        return class_exists($item_class);
+    }
+
+    /**
+     * Process an item (fetch data and convert it)
+     */
+    public function processItem(ItemInterface $item): void
+    {
+        $itemId = ['Id' => $item->id];
+
+        \Log::debug("[EWS] Fetching item {$item->id}...");
 
         // Fetch the item
         $ewsItem = $this->driver->api->getItem($itemId, $this->getItemRequest());
@@ -64,46 +79,48 @@
         \Log::debug("[EWS] Saving item {$uid}...");
 
         // Apply type-specific format converters
-        $content = $this->processItem($ewsItem);
+        $content = $this->convertItem($ewsItem);
 
         if (!is_string($content)) {
-            return;
+            throw new \Exception("Failed to fetch EWS item {$this->itemId}");
         }
 
-        $uid = preg_replace('/[^a-zA-Z0-9_:@-]/', '', $uid);
-
-        $location = $this->folder->location;
+        $filename = $uid . '.' . $this->fileExtension();
 
-        if (!file_exists($location)) {
-            mkdir($location, 0740, true);
-        }
-
-        $location .= '/' . $uid . '.' . $this->fileExtension();
+        if (strlen($content) > Engine::MAX_ITEM_SIZE) {
+            $location = $this->folder->tempFileLocation($filename);
 
-        file_put_contents($location, $content);
+            if (file_put_contents($location, $content) === false) {
+                throw new \Exception("Failed to write to file at {$location}");
+            }
 
-        return $location;
+            $item->filename = $location;
+        } else {
+            $item->content = $content;
+            $item->filename = $filename;
+        }
     }
 
     /**
      * Item conversion code
      */
-    abstract protected function processItem(Type $item);
+    abstract protected function convertItem(Type $item);
 
     /**
      * Get GetItem request parameters
      */
-    protected function getItemRequest(): array
+    protected static function getItemRequest(): array
     {
         $request = [
             'ItemShape' => [
                 // Reqest default set of properties
                 'BaseShape' => 'Default',
                 // Additional properties, e.g. LastModifiedTime
-                // FIXME: How to add multiple properties here?
                 'AdditionalProperties' => [
-                    'FieldURI' => ['FieldURI' => 'item:LastModifiedTime'],
-                ]
+                    'FieldURI' => [
+                        ['FieldURI' => 'item:LastModifiedTime'],
+                    ],
+                ],
             ]
         ];
 
diff --git a/src/app/DataMigrator/EWS/Note.php b/src/app/DataMigrator/EWS/Note.php
--- a/src/app/DataMigrator/EWS/Note.php
+++ b/src/app/DataMigrator/EWS/Note.php
@@ -16,7 +16,7 @@
     /**
      * Get GetItem request parameters
      */
-    protected function getItemRequest(): array
+    protected static function getItemRequest(): array
     {
         $request = parent::getItemRequest();
 
@@ -32,7 +32,7 @@
     /**
      * Process contact object
      */
-    protected function processItem(Type $item)
+    protected function convertItem(Type $item)
     {
         $email = base64_decode((string) $item->getMimeContent());
 
diff --git a/src/app/DataMigrator/EWS/Task.php b/src/app/DataMigrator/EWS/Task.php
--- a/src/app/DataMigrator/EWS/Task.php
+++ b/src/app/DataMigrator/EWS/Task.php
@@ -16,7 +16,7 @@
     /**
      * Get GetItem request parameters
      */
-    protected function getItemRequest(): array
+    protected static function getItemRequest(): array
     {
         $request = parent::getItemRequest();
 
@@ -29,7 +29,7 @@
     /**
      * Process task object
      */
-    protected function processItem(Type $item)
+    protected function convertItem(Type $item)
     {
         // Tasks are exported as Email messages in useless format
         // (does not contain all relevant properties)
diff --git a/src/app/DataMigrator/Engine.php b/src/app/DataMigrator/Engine.php
--- a/src/app/DataMigrator/Engine.php
+++ b/src/app/DataMigrator/Engine.php
@@ -3,6 +3,7 @@
 namespace App\DataMigrator;
 
 use App\DataMigrator\Interface\ExporterInterface;
+use App\DataMigrator\Interface\FetchItemSetInterface;
 use App\DataMigrator\Interface\Folder;
 use App\DataMigrator\Interface\ImporterInterface;
 use App\DataMigrator\Interface\Item;
@@ -21,6 +22,9 @@
     public const TYPE_NOTE = 'note';
     public const TYPE_TASK = 'task';
 
+    /** @const int Max item size to handle in-memory, bigger will be handled with temp files */
+    public const MAX_ITEM_SIZE = 20 * 1024 * 1024;
+
     /** @var Account Source account */
     public $source;
 
@@ -43,7 +47,7 @@
     /**
      * Execute migration for the specified user
      */
-    public function migrate(Account $source, Account $destination, array $options = [])
+    public function migrate(Account $source, Account $destination, array $options = []): void
     {
         $this->source = $source;
         $this->destination = $destination;
@@ -87,14 +91,14 @@
         // Create a queue
         $this->createQueue($queue_id);
 
-        // We'll store output in storage/<username> tree
+        // We'll store temp files in storage/<username> tree
         $location = storage_path('export/') . $source->email;
 
         if (!file_exists($location)) {
             mkdir($location, 0740, true);
         }
 
-        $types = preg_split('/\s*,\s*/', strtolower($options['type'] ?? ''));
+        $types = empty($options['type']) ? [] : preg_split('/\s*,\s*/', strtolower($options['type']));
 
         $this->debug("Fetching folders hierarchy...");
 
@@ -189,8 +193,8 @@
         $this->exporter->fetchItem($item);
         $this->importer->createItem($item);
 
-        if (!empty($item->filename)) {
-            unlink($item->filename);
+        if (!empty($item->filename) && str_starts_with($item->filename, storage_path('export/'))) {
+            @unlink($item->filename);
         }
 
         if (empty($this->options['sync'])) {
@@ -208,15 +212,21 @@
             $this->envFromQueue($set->items[0]->folder->queueId);
         }
 
-        // TODO: Some exporters, e.g. DAV, might optimize fetching multiple items in one go,
-        // we'll need a new API to do that
-
-        foreach ($set->items as $item) {
-            $this->exporter->fetchItem($item);
+        $importItem = function (Item $item) {
             $this->importer->createItem($item);
 
-            if (!empty($item->filename)) {
-                unlink($item->filename);
+            if (!empty($item->filename) && str_starts_with($item->filename, storage_path('export/'))) {
+                @unlink($item->filename);
+            }
+        };
+
+        // Some exporters, e.g. DAV, might optimize fetching multiple items in one go
+        if ($this->exporter instanceof FetchItemSetInterface) {
+            $this->exporter->fetchItemSet($set, $importItem);
+        } else {
+            foreach ($set->items as $item) {
+                $this->exporter->fetchItem($item);
+                $importItem($item);
             }
         }
 
@@ -329,6 +339,10 @@
                 $driver = new IMAP($account, $this);
                 break;
 
+            case 'test':
+                $driver = new Test($account, $this);
+                break;
+
             default:
                 throw new \Exception("Failed to init driver for '{$account->scheme}'");
         }
diff --git a/src/app/DataMigrator/IMAP.php b/src/app/DataMigrator/IMAP.php
--- a/src/app/DataMigrator/IMAP.php
+++ b/src/app/DataMigrator/IMAP.php
@@ -88,7 +88,19 @@
     {
         $mailbox = $item->folder->fullname;
 
-        if ($item->filename) {
+        if (strlen($item->content)) {
+            $result = $this->imap->append(
+                $mailbox,
+                $item->content,
+                $item->data['flags'],
+                $item->data['internaldate'],
+                true
+            );
+
+            if ($result === false) {
+                throw new \Exception("Failed to append IMAP message into {$mailbox}");
+            }
+        } elseif ($item->filename) {
             $result = $this->imap->appendFromFile(
                 $mailbox,
                 $item->filename,
@@ -153,35 +165,36 @@
             || $header->timestamp != $item->existing['timestamp']
             || $header->size != $item->existing['size']
         ) {
-            // Save the message content to a file
-            $location = $item->folder->location;
-
-            if (!file_exists($location)) {
-                mkdir($location, 0740, true);
-            }
+            // Handle message content in memory (up to 20MB), bigger messages will use a temp file
+            if ($header->size > Engine::MAX_ITEM_SIZE) {
+                // Save the message content to a file
+                $location = $item->folder->tempFileLocation($uid . '.eml');
 
-            // TODO: What if parent folder not yet exists?
-            $location .= '/' . $uid . '.eml';
+                $fp = fopen($location, 'w');
 
-            // TODO: We should consider streaming the message, it should be possible
-            // with append() and handlePartBody(), but I don't know if anyone tried that.
-
-            $fp = fopen($location, 'w');
+                if (!$fp) {
+                    throw new \Exception("Failed to open 'php://temp' stream");
+                }
 
-            if (!$fp) {
-                throw new \Exception("Failed to write to {$location}");
+                $result = $this->imap->handlePartBody($mailbox, $uid, true, '', null, null, $fp);
+            } else {
+                $result = $this->imap->handlePartBody($mailbox, $uid, true);
             }
 
-            $result = $this->imap->handlePartBody($mailbox, $uid, true, '', null, null, $fp);
-
             if ($result === false) {
-                fclose($fp);
+                if (!empty($fp)) {
+                    fclose($fp);
+                }
+
                 throw new \Exception("Failed to fetch IMAP message for {$mailbox}/{$uid}");
             }
 
-            $item->filename = $location;
-
-            fclose($fp);
+            if (!empty($fp) && !empty($location)) {
+                $item->filename = $location;
+                fclose($fp);
+            } else {
+                $item->content = $result;
+            }
         }
 
         $item->data = [
diff --git a/src/app/DataMigrator/Interface/FetchItemSetInterface.php b/src/app/DataMigrator/Interface/FetchItemSetInterface.php
new file mode 100644
--- /dev/null
+++ b/src/app/DataMigrator/Interface/FetchItemSetInterface.php
@@ -0,0 +1,14 @@
+<?php
+
+namespace App\DataMigrator\Interface;
+
+interface FetchItemSetInterface
+{
+    /**
+     * Fetching a set of items in one operation
+     *
+     * @param ItemSet  $set      Set of items
+     * @param callable $callback A callback to execute on every Item
+     */
+    public function fetchItemSet(ItemSet $set, $callback): void;
+}
diff --git a/src/app/DataMigrator/Interface/Folder.php b/src/app/DataMigrator/Interface/Folder.php
--- a/src/app/DataMigrator/Interface/Folder.php
+++ b/src/app/DataMigrator/Interface/Folder.php
@@ -34,6 +34,9 @@
     public $queueId;
 
 
+    /**
+     * Create Folder instance from an array
+     */
     public static function fromArray(array $data = []): Folder
     {
         $obj = new self();
@@ -44,4 +47,23 @@
 
         return $obj;
     }
+
+    /**
+     * Returns location of a temp file for an Item content
+     */
+    public function tempFileLocation(string $filename): string
+    {
+        $filename = preg_replace('/[^a-zA-Z0-9_:@.-]/', '', $filename);
+
+        $location = $this->location;
+
+        // TODO: What if parent folder not yet exists?
+        if (!file_exists($location)) {
+            mkdir($location, 0740, true);
+        }
+
+        $location .= '/' . $filename;
+
+        return $location;
+    }
 }
diff --git a/src/app/DataMigrator/Interface/Item.php b/src/app/DataMigrator/Interface/Item.php
--- a/src/app/DataMigrator/Interface/Item.php
+++ b/src/app/DataMigrator/Interface/Item.php
@@ -10,7 +10,7 @@
     /** @var mixed Item identifier */
     public $id;
 
-    /** @var Folder Folder */
+    /** @var ?Folder Folder */
     public $folder;
 
     /** @var string Object class */
@@ -24,13 +24,19 @@
      */
     public $existing;
 
-    /** @var ?string Exported object location in the local storage */
+    /** @var string Exported object content */
+    public $content = '';
+
+    /** @var ?string Exported object content location */
     public $filename;
 
     /** @var array Extra data to migrate (like email flags, internaldate, etc.) */
     public $data = [];
 
 
+    /**
+     * Create Item object from an array
+     */
     public static function fromArray(array $data = []): Item
     {
         $obj = new self();
diff --git a/src/app/DataMigrator/Interface/ItemSet.php b/src/app/DataMigrator/Interface/ItemSet.php
--- a/src/app/DataMigrator/Interface/ItemSet.php
+++ b/src/app/DataMigrator/Interface/ItemSet.php
@@ -5,16 +5,11 @@
 /**
  * Data object representing a set of data items
  */
-class ItemSet
+class ItemSet implements \Serializable
 {
     /** @var array<Item> Items list */
     public $items = [];
 
-    // TODO: Every item has a $folder property, this makes the set
-    // needlesly big when serialized. We should probably store $folder
-    // once with the set and remove it from an item on serialize
-    // and back in unserialize.
-
     /**
      * Create an ItemSet instance
      */
@@ -25,4 +20,26 @@
 
         return $obj;
     }
+
+    public function serialize(): ?string
+    {
+        // Every item has a Folder property, this makes the set
+        // needlesly big when serialized. Make the size more compact.
+        $folder = count($this->items) ? $this->items[0]->folder : null;
+
+        foreach ($this->items as $item) {
+            $item->folder = null;
+        }
+
+        return serialize([$folder, $this->items]);
+    }
+
+    public function unserialize(string $data): void
+    {
+        [$folder, $this->items] = unserialize($data);
+
+        foreach ($this->items as $item) {
+            $item->folder = $folder;
+        }
+    }
 }
diff --git a/src/app/DataMigrator/Test.php b/src/app/DataMigrator/Test.php
new file mode 100644
--- /dev/null
+++ b/src/app/DataMigrator/Test.php
@@ -0,0 +1,153 @@
+<?php
+
+namespace App\DataMigrator;
+
+use App\DataMigrator\Interface\Folder;
+use App\DataMigrator\Interface\ExporterInterface;
+use App\DataMigrator\Interface\ImporterInterface;
+use App\DataMigrator\Interface\Item;
+use App\DataMigrator\Interface\ItemSet;
+
+class Test implements ExporterInterface, ImporterInterface
+{
+    protected const CHUNK_SIZE = 3;
+
+    public static $fetchedItems = [];
+    public static $createdItems = [];
+    public static $createdFolders = [];
+    public static $folders = [];
+
+    /** @var Account Account to operate on */
+    protected $account;
+
+    /** @var Engine Data migrator engine */
+    protected $engine;
+
+
+    /**
+     * Object constructor
+     */
+    public function __construct(Account $account, Engine $engine)
+    {
+        $this->engine = $engine;
+        $this->account = $account;
+    }
+
+    public static function init($folders)
+    {
+        self::$folders = $folders;
+
+        self::$fetchedItems = [];
+        self::$createdItems = [];
+        self::$createdFolders = [];
+    }
+
+    /**
+     * Check user credentials.
+     *
+     * @throws \Exception
+     */
+    public function authenticate(): void
+    {
+    }
+
+    /**
+     * Create an item in a folder.
+     *
+     * @param Item $item Item to import
+     *
+     * @throws \Exception
+     */
+    public function createItem(Item $item): void
+    {
+        self::$createdItems[] = $item;
+    }
+
+    /**
+     * Create a folder.
+     *
+     * @param Folder $folder Folder data
+     *
+     * @throws \Exception on error
+     */
+    public function createFolder(Folder $folder): void
+    {
+        self::$createdFolders[] = $folder;
+    }
+
+    /**
+     * Fetching an item
+     */
+    public function fetchItem(Item $item): void
+    {
+        $item->content = 'content';
+        $item->filename = 'test.eml';
+
+        self::$fetchedItems[] = $item;
+    }
+
+    /**
+     * Fetch a list of folder items
+     */
+    public function fetchItemList(Folder $folder, $callback, ImporterInterface $importer): void
+    {
+        // Get existing messages' headers from the destination mailbox
+        $existing = $importer->getItems($folder);
+
+        $set = new ItemSet();
+
+        foreach ((self::$folders[$folder->id]['items'] ?? []) as $itemId => $item) {
+            $exists = null; // TODO
+
+            $item['id'] = $itemId;
+            $item['folder'] = $folder;
+            $item['existing'] = $exists;
+
+            $set->items[] = Item::fromArray($item);
+
+            if (count($set->items) == self::CHUNK_SIZE) {
+                $callback($set);
+                $set = new ItemSet();
+            }
+        }
+
+        if (count($set->items)) {
+            $callback($set);
+        }
+    }
+
+    /**
+     * Get a list of items, limited to their essential propeties
+     * used in incremental migration.
+     *
+     * @param Folder $folder Folder data
+     *
+     * @throws \Exception on error
+     */
+    public function getItems(Folder $folder): array
+    {
+        return self::$folders[$folder->id]['existing_items'] ?? [];
+    }
+
+    /**
+     * Get folders hierarchy
+     */
+    public function getFolders($types = []): array
+    {
+        $result = [];
+
+        foreach (self::$folders as $folderId => $folder) {
+            // Skip folder types we do not support (need)
+            if (!empty($types) && !in_array($folder['type'], $types)) {
+                continue;
+            }
+
+            $folder['id'] = $folderId;
+            $folder['total'] = count($folder['items']);
+
+            $result[] = Folder::fromArray($folder);
+        }
+
+        return $result;
+    }
+}
diff --git a/src/tests/Feature/DataMigrator/EngineTest.php b/src/tests/Feature/DataMigrator/EngineTest.php
--- a/src/tests/Feature/DataMigrator/EngineTest.php
+++ b/src/tests/Feature/DataMigrator/EngineTest.php
@@ -4,11 +4,53 @@
 
 use App\DataMigrator\Account;
 use App\DataMigrator\Engine;
+use App\DataMigrator\Jobs\FolderJob;
+use App\DataMigrator\Jobs\ItemJob;
 use App\DataMigrator\Queue as MigratorQueue;
+use App\DataMigrator\Test;
+use Illuminate\Support\Facades\Queue;
 use Tests\TestCase;
 
 class EngineTest extends TestCase
 {
+    protected $data = [
+        'Inbox' => [
+            'type' => Engine::TYPE_MAIL,
+            'name' => 'Inbox',
+            'fullname' => 'Inbox',
+            'items' => [
+                'm1' => [],
+                'm2' => [],
+                'm3' => [],
+                'm4' => [],
+            ],
+            'existing_items' => [
+            ],
+        ],
+        'Contacts' => [
+            'type' => Engine::TYPE_CONTACT,
+            'name' => 'Contacts',
+            'fullname' => 'Contacts',
+            'items' => [
+                'c1' => [],
+                'c2' => [],
+            ],
+            'existing_items' => [
+            ],
+        ],
+        'Calendar' => [
+            'type' => Engine::TYPE_EVENT,
+            'name' => 'Calendar',
+            'fullname' => 'Calendar',
+            'items' => [
+                'e1' => [],
+                'e2' => [],
+            ],
+            'existing_items' => [
+            ],
+        ],
+    ];
+
     /**
      * {@inheritDoc}
      */
@@ -34,6 +76,48 @@
      */
     public function testAsyncMigration(): void
     {
+        $source = new Account('test://test%40domain.tld:test@test');
+        $destination = new Account('test://test%40kolab.org:test@test');
+        $engine = new Engine();
+
+        Test::init($this->data);
+        Queue::fake();
+
+        // Migration initial run
+        $engine->migrate($source, $destination, []);
+
+        $queue = MigratorQueue::first();
+
+        Queue::assertPushed(FolderJob::class, 3);
+        Queue::assertPushed(
+            FolderJob::class,
+            function ($job) use ($queue) {
+                $folder = TestCase::getObjectProperty($job, 'folder');
+                return $folder->id === 'Inbox' && $folder->queueId = $queue->id;
+            }
+        );
+        Queue::assertPushed(
+            FolderJob::class,
+            function ($job) use ($queue) {
+                $folder = TestCase::getObjectProperty($job, 'folder');
+                return $folder->id === 'Contacts' && $folder->queueId = $queue->id;
+            }
+        );
+        Queue::assertPushed(
+            FolderJob::class,
+            function ($job) use ($queue) {
+                $folder = TestCase::getObjectProperty($job, 'folder');
+                return $folder->id === 'Calendar' && $folder->queueId = $queue->id;
+            }
+        );
+
+        $this->assertCount(0, Test::$createdFolders);
+        $this->assertSame(3, $queue->jobs_started);
+        $this->assertSame(0, $queue->jobs_finished);
+        $this->assertSame([], $queue->data['options']);
+        // TODO: Assert Source and destination in the queue
+        // TODO: Test 'force' option, test executing with an existing queue
+        // TODO: Test jobs execution
         $this->markTestIncomplete();
     }
 
@@ -42,6 +126,42 @@
      */
     public function testSyncMigration(): void
     {
-        $this->markTestIncomplete();
+        $source = new Account('test://test%40domain.tld:test@test');
+        $destination = new Account('test://test%40kolab.org:test@test');
+        $engine = new Engine();
+
+        Test::init($this->data);
+        Queue::fake();
+
+        $engine->migrate($source, $destination, ['sync' => true]);
+
+        $queue = MigratorQueue::first();
+
+        Queue::assertNothingPushed();
+
+        $this->assertSame(0, $queue->jobs_started);
+        $this->assertSame(0, $queue->jobs_finished);
+        $this->assertSame(['sync' => true], $queue->data['options']);
+
+        $this->assertCount(3, Test::$createdFolders);
+        $this->assertCount(8, Test::$createdItems);
+        $this->assertCount(8, Test::$fetchedItems);
+
+        Test::init($this->data);
+
+        // Test 'type' argument
+        $engine->migrate($source, $destination, ['sync' => true, 'type' => 'contact,event']);
+
+        $queue = MigratorQueue::whereNot('id', $queue->id)->first();
+
+        Queue::assertNothingPushed();
+
+        $this->assertSame(0, $queue->jobs_started);
+        $this->assertSame(0, $queue->jobs_finished);
+        $this->assertSame(['sync' => true, 'type' => 'contact,event'], $queue->data['options']);
+
+        $this->assertCount(2, Test::$createdFolders);
+        $this->assertCount(4, Test::$createdItems);
+        $this->assertCount(4, Test::$fetchedItems);
     }
 }
diff --git a/src/tests/Feature/DomainTest.php b/src/tests/Feature/DomainTest.php
--- a/src/tests/Feature/DomainTest.php
+++ b/src/tests/Feature/DomainTest.php
@@ -138,9 +138,6 @@
                     $domainNamespace === $domain->namespace;
             }
         );
-
-        $job = new \App\Jobs\Domain\CreateJob($domain->id);
-        $job->handle();
     }
 
     /**
diff --git a/src/tests/Unit/DataMigrator/EWS/AppointmentTest.php b/src/tests/Unit/DataMigrator/EWS/AppointmentTest.php
--- a/src/tests/Unit/DataMigrator/EWS/AppointmentTest.php
+++ b/src/tests/Unit/DataMigrator/EWS/AppointmentTest.php
@@ -15,7 +15,7 @@
     /**
      * Test appointment item processing
      */
-    public function testProcessItem(): void
+    public function testConvertItem(): void
     {
         $account = new Account('ews://test:test@test');
         $engine = new Engine();
@@ -78,7 +78,7 @@
         ]);
 
         // Convert the Exchange item into iCalendar
-        $ical = $this->invokeMethod($appointment, 'processItem', [$item]);
+        $ical = $this->invokeMethod($appointment, 'convertItem', [$item]);
 
         // Parse the iCalendar output
         $event = new Vevent();
diff --git a/src/tests/Unit/DataMigrator/EWS/ContactTest.php b/src/tests/Unit/DataMigrator/EWS/ContactTest.php
--- a/src/tests/Unit/DataMigrator/EWS/ContactTest.php
+++ b/src/tests/Unit/DataMigrator/EWS/ContactTest.php
@@ -15,7 +15,7 @@
     /**
      * Test contact item processing
      */
-    public function testProcessItem(): void
+    public function testConvertItem(): void
     {
         $account = new Account('ews://test:test@test');
         $engine = new Engine();
@@ -113,7 +113,7 @@
         ]);
 
         // Convert the Exchange item into vCard
-        $vcard = $this->invokeMethod($contact, 'processItem', [$item]);
+        $vcard = $this->invokeMethod($contact, 'convertItem', [$item]);
 
         // Parse the vCard
         $contact = new Vcard();
diff --git a/src/tests/Unit/DataMigrator/EWS/DistListTest.php b/src/tests/Unit/DataMigrator/EWS/DistListTest.php
--- a/src/tests/Unit/DataMigrator/EWS/DistListTest.php
+++ b/src/tests/Unit/DataMigrator/EWS/DistListTest.php
@@ -15,7 +15,7 @@
     /**
      * Test contact item processing
      */
-    public function testProcessItem(): void
+    public function testConvertItem(): void
     {
         $account = new Account('ews://test:test@test');
         $engine = new Engine();
@@ -37,6 +37,11 @@
             'LastModifiedTime' => '2024-06-27T13:44:32Z',
             'DisplayName' => 'Lista',
             'FileAs' => 'lista',
+            'Body' => [
+                'BodyType' => 'Text',
+                'IsTruncated' => false,
+                '_value' => 'distlist body',
+            ],
             'Members' => (object) [
                 'Member' => [
                     Type\MemberType::buildFromArray([
@@ -67,7 +72,7 @@
         ]);
 
         // Convert the Exchange item into vCard
-        $vcard = $this->invokeMethod($distlist, 'processItem', [$item]);
+        $vcard = $this->invokeMethod($distlist, 'convertItem', [$item]);
 
         // Parse the vCard
         $distlist = new Vcard();
@@ -78,6 +83,7 @@
         $this->assertMatchesRegularExpression('/^[a-f0-9]{40}$/', $distlist->uid);
         $this->assertSame('group', $distlist->kind);
         $this->assertSame('Lista', $distlist->fn);
+        $this->assertSame('distlist body', $distlist->note);
         $this->assertSame('Kolab EWS Data Migrator', $distlist->prodid);
         $this->assertSame('2024-06-27T13:44:32Z', $distlist->rev);
 
diff --git a/src/tests/Unit/DataMigrator/EWS/TaskTest.php b/src/tests/Unit/DataMigrator/EWS/TaskTest.php
--- a/src/tests/Unit/DataMigrator/EWS/TaskTest.php
+++ b/src/tests/Unit/DataMigrator/EWS/TaskTest.php
@@ -15,7 +15,7 @@
     /**
      * Test task item processing
      */
-    public function testProcessItem(): void
+    public function testConvertItem(): void
     {
         $source = new Account('ews://test%40domain.tld:test@test');
         $destination = new Account('dav://test%40kolab.org:test@test');
@@ -118,7 +118,7 @@
         ]);
 
         // Convert the Exchange item into iCalendar
-        $ical = $this->invokeMethod($task, 'processItem', [$item]);
+        $ical = $this->invokeMethod($task, 'convertItem', [$item]);
 
         // Parse the iCalendar output
         $task = new Vtodo();
@@ -154,7 +154,7 @@
     /**
      * Test processing Recurrence property
      */
-    public function testProcessItemRecurrence(): void
+    public function testConvertItemRecurrence(): void
     {
         $this->markTestIncomplete();
     }