diff --git a/app/Classes/AttachmentsManager.php b/app/Classes/AttachmentsManager.php
index a3f0d6d..a3cff24 100644
--- a/app/Classes/AttachmentsManager.php
+++ b/app/Classes/AttachmentsManager.php
@@ -4,6 +4,7 @@
 
 use App\Classes\Traits\ManagesMetadata;
 use Illuminate\Filesystem\FilesystemAdapter;
+use Illuminate\Support\Facades\Http;
 use Illuminate\Support\Str;
 
 class AttachmentsManager
@@ -47,10 +48,14 @@ public function addToHistory(string $name, array $data): string
     {
         $reference = $this->add($data);
 
-        $this->manager['history'][$name][] = [
-            'reference' => $reference,
-            'date'      => now(),
-        ];
+        $this->manager->merge([
+            'history' => [
+                $name => [
+                    'reference' => $reference,
+                    'date'      => now(),
+                ],
+            ],
+        ]);
 
         return $reference;
     }
@@ -63,15 +68,6 @@ public function manager(): MetadataManager
         return $this->manager;
     }
 
-    /**
-     * Add or replace attachment with specified reference. Will replace existing
-     * data
-     */
-    public function upsert(string $reference, array $data)
-    {
-        $this->manager['files'][$reference] = $data;
-    }
-
     /**
      * Add a single file to the bundle
      */
@@ -79,11 +75,22 @@ public function add(array $data): string
     {
         $reference = $this->generateNewReference();
 
-        $filename = $data['filename'];
-        $contents = $data['contents'];
+        if (!empty($data['contents'])) {
+            // Adding from an image resource of which $data['contents'] is a
+            // representation
+            $contents = $data['contents'];
 
-        unset($data['contents']);
+            unset($data['contents']);
+        } elseif (!empty($data['url'])) {
+            // Adding from a URL which implies downloading the resource
+            $contents = Http::throw()->get($data['url'])->body();
 
+            $data['filename'] = basename($data['url']);
+
+            unset($data['url']);
+        }
+
+        $filename     = $this->getFormatedFilename($data['filename']);
         $fullPath     = sprintf('%s/%s', $this->targetForFiles, $filename);
         $relativePath = sprintf('%s/%s/%s', $this->attachmentsDir, $this->kind, $filename);
 
@@ -91,11 +98,20 @@ public function add(array $data): string
 
         $this->disk->put($fullPath, $contents);
 
-        $this->manager['files'][$reference] = $data;
+        $this->manager->set(sprintf('files.%s', $reference), $data);
 
         return $reference;
     }
 
+    private function getFormatedFilename(string $path): string
+    {
+        $filename  = pathinfo($path, PATHINFO_FILENAME);
+        $extension = pathinfo($path, PATHINFO_EXTENSION);
+        $slug      = Str::slug($filename);
+
+        return sprintf('%s.%s', $slug, $extension);
+    }
+
     /**
      * Return a boolean value indicating if the file actually exists on disk
      */
diff --git a/app/Classes/MetadataManager.php b/app/Classes/MetadataManager.php
index 2ab28f4..fbed3d0 100644
--- a/app/Classes/MetadataManager.php
+++ b/app/Classes/MetadataManager.php
@@ -100,17 +100,32 @@ protected function writeToDisk(array $data)
      */
     public function set($key, $value)
     {
-        $this->setMany(collect([$key => $value])->undot());
+        $content    = $this->content->dot();
+        $newValue   = collect([$key => $value])->dot();
+        $newContent = collect($content)->replaceRecursive($newValue)->undot();
+
+        $this->content = $newContent;
     }
 
     /**
-     * Sets multiple metadata at once.
+     * Set many values at once
      */
-    public function setMany($array)
+    public function setMany(array $array)
     {
-        foreach ($array as $key => $value) {
-            $this->content->put($key, $value);
-        }
+        $content    = $this->content->dot();
+        $newValue   = collect($array)->dot();
+        $newContent = collect($content)->replaceRecursive($newValue)->undot();
+
+        $this->content = $newContent;
+    }
+
+    public function merge(array $array)
+    {
+        $content    = $this->content->dot();
+        $newValue   = collect($array)->dot();
+        $newContent = collect($content)->mergeRecursive($newValue)->undot();
+
+        $this->content = $newContent;
     }
 
     /**