diff --git a/src/applications/diffusion/query/DiffusionPullLogSearchEngine.php b/src/applications/diffusion/query/DiffusionPullLogSearchEngine.php
--- a/src/applications/diffusion/query/DiffusionPullLogSearchEngine.php
+++ b/src/applications/diffusion/query/DiffusionPullLogSearchEngine.php
@@ -49,12 +49,6 @@
 
   protected function newExportFields() {
     return array(
-      id(new PhabricatorIDExportField())
-        ->setKey('id')
-        ->setLabel(pht('ID')),
-      id(new PhabricatorPHIDExportField())
-        ->setKey('phid')
-        ->setLabel(pht('PHID')),
       id(new PhabricatorPHIDExportField())
         ->setKey('repositoryPHID')
         ->setLabel(pht('Repository PHID')),
@@ -82,7 +76,7 @@
     );
   }
 
-  public function newExport(array $events) {
+  protected function newExportData(array $events) {
     $viewer = $this->requireViewer();
 
     $phids = array();
@@ -112,8 +106,6 @@
       }
 
       $export[] = array(
-        'id' => $event->getID(),
-        'phid' => $event->getPHID(),
         'repositoryPHID' => $repository_phid,
         'repository' => $repository_name,
         'pullerPHID' => $puller_phid,
diff --git a/src/applications/people/query/PhabricatorPeopleSearchEngine.php b/src/applications/people/query/PhabricatorPeopleSearchEngine.php
--- a/src/applications/people/query/PhabricatorPeopleSearchEngine.php
+++ b/src/applications/people/query/PhabricatorPeopleSearchEngine.php
@@ -322,12 +322,6 @@
 
   protected function newExportFields() {
     return array(
-      id(new PhabricatorIDExportField())
-        ->setKey('id')
-        ->setLabel(pht('ID')),
-      id(new PhabricatorPHIDExportField())
-        ->setKey('phid')
-        ->setLabel(pht('PHID')),
       id(new PhabricatorStringExportField())
         ->setKey('username')
         ->setLabel(pht('Username')),
@@ -340,14 +334,12 @@
     );
   }
 
-  public function newExport(array $users) {
+  protected function newExportData(array $users) {
     $viewer = $this->requireViewer();
 
     $export = array();
     foreach ($users as $user) {
       $export[] = array(
-        'id' => $user->getID(),
-        'phid' => $user->getPHID(),
         'username' => $user->getUsername(),
         'realName' => $user->getRealName(),
         'created' => $user->getDateCreated(),
diff --git a/src/applications/search/controller/PhabricatorApplicationSearchController.php b/src/applications/search/controller/PhabricatorApplicationSearchController.php
--- a/src/applications/search/controller/PhabricatorApplicationSearchController.php
+++ b/src/applications/search/controller/PhabricatorApplicationSearchController.php
@@ -449,18 +449,7 @@
         $format->setViewer($viewer);
 
         $export_data = $engine->newExport($objects);
-
-        if (count($export_data) !== count($objects)) {
-          throw new Exception(
-            pht(
-              'Search engine exported the wrong number of objects, expected '.
-              '%s but got %s.',
-              phutil_count($objects),
-              phutil_count($export_data)));
-        }
-
         $objects = array_values($objects);
-        $export_data = array_values($export_data);
 
         $field_list = $engine->newExportFieldList();
         $field_list = mpull($field_list, null, 'getKey');
diff --git a/src/applications/search/engine/PhabricatorApplicationSearchEngine.php b/src/applications/search/engine/PhabricatorApplicationSearchEngine.php
--- a/src/applications/search/engine/PhabricatorApplicationSearchEngine.php
+++ b/src/applications/search/engine/PhabricatorApplicationSearchEngine.php
@@ -1455,11 +1455,74 @@
   }
 
   final public function newExportFieldList() {
-    return $this->newExportFields();
+    $builtin_fields = array(
+      id(new PhabricatorIDExportField())
+        ->setKey('id')
+        ->setLabel(pht('ID')),
+      id(new PhabricatorPHIDExportField())
+        ->setKey('phid')
+        ->setLabel(pht('PHID')),
+    );
+
+    $fields = mpull($builtin_fields, null, 'getKey');
+
+    $export_fields = $this->newExportFields();
+    foreach ($export_fields as $export_field) {
+      $key = $export_field->getKey();
+
+      if (isset($fields[$key])) {
+        throw new Exception(
+          pht(
+            'Search engine ("%s") defines an export field with a key ("%s") '.
+            'that collides with another field. Each field must have a '.
+            'unique key.',
+            get_class($this),
+            $key));
+      }
+
+      $fields[$key] = $export_field;
+    }
+
+    return $fields;
+  }
+
+  final public function newExport(array $objects) {
+    $objects = array_values($objects);
+    $n = count($objects);
+
+    $maps = array();
+    foreach ($objects as $object) {
+      $maps[] = array(
+        'id' => $object->getID(),
+        'phid' => $object->getPHID(),
+      );
+    }
+
+    $export_data = $this->newExportData($objects);
+    $export_data = array_values($export_data);
+    if (count($export_data) !== count($objects)) {
+      throw new Exception(
+        pht(
+          'Search engine ("%s") exported the wrong number of objects, '.
+          'expected %s but got %s.',
+          get_class($this),
+          phutil_count($objects),
+          phutil_count($export_data)));
+    }
+
+    for ($ii = 0; $ii < $n; $ii++) {
+      $maps[$ii] += $export_data[$ii];
+    }
+
+    return $maps;
   }
 
   protected function newExportFields() {
     return array();
   }
 
+  protected function newExportData(array $objects) {
+    throw new PhutilMethodNotImplementedException();
+  }
+
 }