diff --git a/resources/sql/autopatches/20220510.file.01.attach.sql b/resources/sql/autopatches/20220510.file.01.attach.sql
new file mode 100644
--- /dev/null
+++ b/resources/sql/autopatches/20220510.file.01.attach.sql
@@ -0,0 +1,9 @@
+CREATE TABLE {$NAMESPACE}_file.file_attachment (
+  id INT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY,
+  objectPHID VARBINARY(64) NOT NULL,
+  filePHID VARBINARY(64) NOT NULL,
+  attacherPHID VARBINARY(64),
+  attachmentMode VARCHAR(32) NOT NULL COLLATE {$COLLATE_TEXT},
+  dateCreated INT UNSIGNED NOT NULL,
+  dateModified INT UNSIGNED NOT NULL
+) ENGINE=InnoDB, COLLATE {$COLLATE_TEXT};
diff --git a/src/__phutil_library_map__.php b/src/__phutil_library_map__.php
--- a/src/__phutil_library_map__.php
+++ b/src/__phutil_library_map__.php
@@ -3450,6 +3450,7 @@
     'PhabricatorFile' => 'applications/files/storage/PhabricatorFile.php',
     'PhabricatorFileAES256StorageFormat' => 'applications/files/format/PhabricatorFileAES256StorageFormat.php',
     'PhabricatorFileAltTextTransaction' => 'applications/files/xaction/PhabricatorFileAltTextTransaction.php',
+    'PhabricatorFileAttachment' => 'applications/files/storage/PhabricatorFileAttachment.php',
     'PhabricatorFileBundleLoader' => 'applications/files/query/PhabricatorFileBundleLoader.php',
     'PhabricatorFileChunk' => 'applications/files/storage/PhabricatorFileChunk.php',
     'PhabricatorFileChunkIterator' => 'applications/files/engine/PhabricatorFileChunkIterator.php',
@@ -9888,6 +9889,7 @@
     ),
     'PhabricatorFileAES256StorageFormat' => 'PhabricatorFileStorageFormat',
     'PhabricatorFileAltTextTransaction' => 'PhabricatorFileTransactionType',
+    'PhabricatorFileAttachment' => 'PhabricatorFileDAO',
     'PhabricatorFileBundleLoader' => 'Phobject',
     'PhabricatorFileChunk' => array(
       'PhabricatorFileDAO',
diff --git a/src/applications/files/storage/PhabricatorFileAttachment.php b/src/applications/files/storage/PhabricatorFileAttachment.php
new file mode 100644
--- /dev/null
+++ b/src/applications/files/storage/PhabricatorFileAttachment.php
@@ -0,0 +1,31 @@
+<?php
+
+final class PhabricatorFileAttachment
+  extends PhabricatorFileDAO {
+
+  protected $objectPHID;
+  protected $filePHID;
+  protected $attacherPHID;
+  protected $attachmentMode;
+
+  protected function getConfiguration() {
+    return array(
+      self::CONFIG_COLUMN_SCHEMA => array(
+        'objectPHID' => 'phid',
+        'filePHID' => 'phid',
+        'attacherPHID' => 'phid?',
+        'attachmentMode' => 'text32',
+      ),
+      self::CONFIG_KEY_SCHEMA => array(
+        'key_object' => array(
+          'columns' => array('objectPHID', 'filePHID'),
+          'unique' => true,
+        ),
+        'key_file' => array(
+          'columns' => array('filePHID'),
+        ),
+      ),
+    ) + parent::getConfiguration();
+  }
+
+}