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
@@ -2836,7 +2836,6 @@
     'PhabricatorProfilePanelEditor' => 'applications/search/editor/PhabricatorProfilePanelEditor.php',
     'PhabricatorProfilePanelEngine' => 'applications/search/engine/PhabricatorProfilePanelEngine.php',
     'PhabricatorProfilePanelIconSet' => 'applications/search/profilepanel/PhabricatorProfilePanelIconSet.php',
-    'PhabricatorProfilePanelInterface' => 'applications/search/interface/PhabricatorProfilePanelInterface.php',
     'PhabricatorProfilePanelPHIDType' => 'applications/search/phidtype/PhabricatorProfilePanelPHIDType.php',
     'PhabricatorProject' => 'applications/project/storage/PhabricatorProject.php',
     'PhabricatorProjectAddHeraldAction' => 'applications/project/herald/PhabricatorProjectAddHeraldAction.php',
@@ -2902,6 +2901,7 @@
     'PhabricatorProjectPHIDResolver' => 'applications/phid/resolver/PhabricatorProjectPHIDResolver.php',
     'PhabricatorProjectPanelController' => 'applications/project/controller/PhabricatorProjectPanelController.php',
     'PhabricatorProjectProfileController' => 'applications/project/controller/PhabricatorProjectProfileController.php',
+    'PhabricatorProjectProfilePanelEngine' => 'applications/project/engine/PhabricatorProjectProfilePanelEngine.php',
     'PhabricatorProjectProjectHasMemberEdgeType' => 'applications/project/edge/PhabricatorProjectProjectHasMemberEdgeType.php',
     'PhabricatorProjectProjectHasObjectEdgeType' => 'applications/project/edge/PhabricatorProjectProjectHasObjectEdgeType.php',
     'PhabricatorProjectProjectPHIDType' => 'applications/project/phid/PhabricatorProjectProjectPHIDType.php',
@@ -7214,7 +7214,6 @@
       'PhabricatorDestructibleInterface',
       'PhabricatorFulltextInterface',
       'PhabricatorConduitResultInterface',
-      'PhabricatorProfilePanelInterface',
     ),
     'PhabricatorProjectAddHeraldAction' => 'PhabricatorProjectHeraldAction',
     'PhabricatorProjectApplication' => 'PhabricatorApplication',
@@ -7289,6 +7288,7 @@
     'PhabricatorProjectPHIDResolver' => 'PhabricatorPHIDResolver',
     'PhabricatorProjectPanelController' => 'PhabricatorProjectController',
     'PhabricatorProjectProfileController' => 'PhabricatorProjectController',
+    'PhabricatorProjectProfilePanelEngine' => 'PhabricatorProfilePanelEngine',
     'PhabricatorProjectProjectHasMemberEdgeType' => 'PhabricatorEdgeType',
     'PhabricatorProjectProjectHasObjectEdgeType' => 'PhabricatorEdgeType',
     'PhabricatorProjectProjectPHIDType' => 'PhabricatorPHIDType',
diff --git a/src/applications/project/controller/PhabricatorProjectController.php b/src/applications/project/controller/PhabricatorProjectController.php
--- a/src/applications/project/controller/PhabricatorProjectController.php
+++ b/src/applications/project/controller/PhabricatorProjectController.php
@@ -102,7 +102,7 @@
       if ($project) {
         $viewer = $this->getViewer();
 
-        $engine = id(new PhabricatorProfilePanelEngine())
+        $engine = id(new PhabricatorProjectProfilePanelEngine())
           ->setViewer($viewer)
           ->setProfileObject($project);
 
diff --git a/src/applications/project/controller/PhabricatorProjectPanelController.php b/src/applications/project/controller/PhabricatorProjectPanelController.php
--- a/src/applications/project/controller/PhabricatorProjectPanelController.php
+++ b/src/applications/project/controller/PhabricatorProjectPanelController.php
@@ -12,7 +12,7 @@
     $viewer = $this->getViewer();
     $project = $this->getProject();
 
-    return id(new PhabricatorProfilePanelEngine())
+    return id(new PhabricatorProjectProfilePanelEngine())
       ->setProfileObject($project)
       ->setController($this)
       ->buildResponse();
diff --git a/src/applications/project/engine/PhabricatorProjectProfilePanelEngine.php b/src/applications/project/engine/PhabricatorProjectProfilePanelEngine.php
new file mode 100644
--- /dev/null
+++ b/src/applications/project/engine/PhabricatorProjectProfilePanelEngine.php
@@ -0,0 +1,51 @@
+<?php
+
+final class PhabricatorProjectProfilePanelEngine
+  extends PhabricatorProfilePanelEngine {
+
+  protected function getPanelURI($path) {
+    $project = $this->getProfileObject();
+    $id = $project->getID();
+    return "/project/{$id}/panel/{$path}";
+  }
+
+  protected function getBuiltinProfilePanels($object) {
+    $panels = array();
+
+    $panels[] = $this->newPanel()
+      ->setBuiltinKey(PhabricatorProject::PANEL_PROFILE)
+      ->setPanelKey(PhabricatorProjectDetailsProfilePanel::PANELKEY);
+
+    $panels[] = $this->newPanel()
+      ->setBuiltinKey(PhabricatorProject::PANEL_WORKBOARD)
+      ->setPanelKey(PhabricatorProjectWorkboardProfilePanel::PANELKEY);
+
+    // TODO: This is temporary.
+    $uri = urisprintf(
+      '/maniphest/?statuses=open()&projects=%s#R',
+      $object->getPHID());
+
+    $panels[] = $this->newPanel()
+      ->setBuiltinKey('tasks')
+      ->setPanelKey(PhabricatorLinkProfilePanel::PANELKEY)
+      ->setPanelProperty('icon', 'maniphest')
+      ->setPanelProperty('name', pht('Open Tasks'))
+      ->setPanelProperty('uri', $uri);
+
+    // TODO: This is temporary.
+    $id = $object->getID();
+    $panels[] = $this->newPanel()
+      ->setBuiltinKey('feed')
+      ->setPanelKey(PhabricatorLinkProfilePanel::PANELKEY)
+      ->setPanelProperty('icon', 'feed')
+      ->setPanelProperty('name', pht('Feed'))
+      ->setPanelProperty('uri', "/project/feed/{$id}/");
+
+    $panels[] = $this->newPanel()
+      ->setBuiltinKey(PhabricatorProject::PANEL_MEMBERS)
+      ->setPanelKey(PhabricatorProjectMembersProfilePanel::PANELKEY);
+
+    return $panels;
+  }
+
+}
diff --git a/src/applications/project/storage/PhabricatorProject.php b/src/applications/project/storage/PhabricatorProject.php
--- a/src/applications/project/storage/PhabricatorProject.php
+++ b/src/applications/project/storage/PhabricatorProject.php
@@ -10,8 +10,7 @@
     PhabricatorCustomFieldInterface,
     PhabricatorDestructibleInterface,
     PhabricatorFulltextInterface,
-    PhabricatorConduitResultInterface,
-    PhabricatorProfilePanelInterface {
+    PhabricatorConduitResultInterface {
 
   protected $name;
   protected $status = PhabricatorProjectStatus::STATUS_ACTIVE;
@@ -651,47 +650,4 @@
     return array();
   }
 
-
-/* -(  PhabricatorProfilePanelInterface  )----------------------------------- */
-
-
-  public function getBuiltinProfilePanels() {
-    $panels = array();
-
-    $panels[] = PhabricatorProfilePanelConfiguration::initializeNewBuiltin()
-      ->setBuiltinKey(self::PANEL_PROFILE)
-      ->setPanelKey(PhabricatorProjectDetailsProfilePanel::PANELKEY);
-
-    $panels[] = PhabricatorProfilePanelConfiguration::initializeNewBuiltin()
-      ->setBuiltinKey(self::PANEL_WORKBOARD)
-      ->setPanelKey(PhabricatorProjectWorkboardProfilePanel::PANELKEY);
-
-    // TODO: This is temporary.
-    $uri = urisprintf(
-      '/maniphest/?statuses=open()&projects=%s#R',
-      $this->getPHID());
-
-    $panels[] = PhabricatorProfilePanelConfiguration::initializeNewBuiltin()
-      ->setBuiltinKey('tasks')
-      ->setPanelKey(PhabricatorLinkProfilePanel::PANELKEY)
-      ->setPanelProperty('icon', 'maniphest')
-      ->setPanelProperty('name', pht('Open Tasks'))
-      ->setPanelProperty('uri', $uri);
-
-    // TODO: This is temporary.
-    $id = $this->getID();
-    $panels[] = PhabricatorProfilePanelConfiguration::initializeNewBuiltin()
-      ->setBuiltinKey('feed')
-      ->setPanelKey(PhabricatorLinkProfilePanel::PANELKEY)
-      ->setPanelProperty('icon', 'feed')
-      ->setPanelProperty('name', pht('Feed'))
-      ->setPanelProperty('uri', "/project/feed/{$id}/");
-
-    $panels[] = PhabricatorProfilePanelConfiguration::initializeNewBuiltin()
-      ->setBuiltinKey(self::PANEL_MEMBERS)
-      ->setPanelKey(PhabricatorProjectMembersProfilePanel::PANELKEY);
-
-    return $panels;
-  }
-
 }
diff --git a/src/applications/search/editor/PhabricatorProfilePanelEditEngine.php b/src/applications/search/editor/PhabricatorProfilePanelEditEngine.php
--- a/src/applications/search/editor/PhabricatorProfilePanelEditEngine.php
+++ b/src/applications/search/editor/PhabricatorProfilePanelEditEngine.php
@@ -23,8 +23,7 @@
     return $this->panelEngine;
   }
 
-  public function setProfileObject(
-    PhabricatorProfilePanelInterface $profile_object) {
+  public function setProfileObject($profile_object) {
     $this->profileObject = $profile_object;
     return $this;
   }
diff --git a/src/applications/search/engine/PhabricatorProfilePanelEngine.php b/src/applications/search/engine/PhabricatorProfilePanelEngine.php
--- a/src/applications/search/engine/PhabricatorProfilePanelEngine.php
+++ b/src/applications/search/engine/PhabricatorProfilePanelEngine.php
@@ -1,6 +1,6 @@
 <?php
 
-final class PhabricatorProfilePanelEngine extends Phobject {
+abstract class PhabricatorProfilePanelEngine extends Phobject {
 
   private $viewer;
   private $profileObject;
@@ -16,8 +16,7 @@
     return $this->viewer;
   }
 
-  public function setProfileObject(
-    PhabricatorProfilePanelInterface $profile_object) {
+  public function setProfileObject($profile_object) {
     $this->profileObject = $profile_object;
     return $this;
   }
@@ -35,6 +34,8 @@
     return $this->controller;
   }
 
+  abstract protected function getPanelURI($path);
+
   public function buildResponse() {
     $controller = $this->getController();
 
@@ -132,7 +133,7 @@
   public function buildNavigation() {
     $nav = id(new AphrontSideNavFilterView())
       ->setIsProfileMenu(true)
-      ->setBaseURI(new PhutilURI('/project/'));
+      ->setBaseURI(new PhutilURI($this->getPanelURI('')));
 
     $panels = $this->getPanels();
 
@@ -225,7 +226,7 @@
 
   private function loadBuiltinProfilePanels() {
     $object = $this->getProfileObject();
-    $builtins = $object->getBuiltinProfilePanels();
+    $builtins = $this->getBuiltinProfilePanels($object);
 
     $panels = PhabricatorProfilePanel::getAllPanels();
 
@@ -310,12 +311,6 @@
     return $this->getPanelURI('configure/');
   }
 
-  private function getPanelURI($path) {
-    $project = $this->getProfileObject();
-    $id = $project->getID();
-    return "/project/{$id}/panel/{$path}";
-  }
-
   private function buildPanelReorderContent(array $panels) {
     $viewer = $this->getViewer();
     $object = $this->getProfileObject();
@@ -646,4 +641,8 @@
       ->addSubmitButton(pht('Save Changes'));
   }
 
+  protected function newPanel() {
+    return PhabricatorProfilePanelConfiguration::initializeNewBuiltin();
+  }
+
 }
diff --git a/src/applications/search/interface/PhabricatorProfilePanelInterface.php b/src/applications/search/interface/PhabricatorProfilePanelInterface.php
deleted file mode 100644
--- a/src/applications/search/interface/PhabricatorProfilePanelInterface.php
+++ /dev/null
@@ -1,7 +0,0 @@
-<?php
-
-interface PhabricatorProfilePanelInterface {
-
-  public function getBuiltinProfilePanels();
-
-}
diff --git a/src/applications/search/profilepanel/PhabricatorLinkProfilePanel.php b/src/applications/search/profilepanel/PhabricatorLinkProfilePanel.php
--- a/src/applications/search/profilepanel/PhabricatorLinkProfilePanel.php
+++ b/src/applications/search/profilepanel/PhabricatorLinkProfilePanel.php
@@ -13,8 +13,7 @@
     return pht('Link');
   }
 
-  public function canAddToObject(
-    PhabricatorProfilePanelInterface $object) {
+  public function canAddToObject($object) {
     return true;
   }
 
diff --git a/src/applications/search/profilepanel/PhabricatorProfilePanel.php b/src/applications/search/profilepanel/PhabricatorProfilePanel.php
--- a/src/applications/search/profilepanel/PhabricatorProfilePanel.php
+++ b/src/applications/search/profilepanel/PhabricatorProfilePanel.php
@@ -26,8 +26,7 @@
     return array();
   }
 
-  public function canAddToObject(
-    PhabricatorProfilePanelInterface $object) {
+  public function canAddToObject($object) {
     return false;
   }
 
diff --git a/src/applications/search/storage/PhabricatorProfilePanelConfiguration.php b/src/applications/search/storage/PhabricatorProfilePanelConfiguration.php
--- a/src/applications/search/storage/PhabricatorProfilePanelConfiguration.php
+++ b/src/applications/search/storage/PhabricatorProfilePanelConfiguration.php
@@ -26,7 +26,7 @@
   }
 
   public static function initializeNewPanelConfiguration(
-    PhabricatorProfilePanelInterface $profile_object,
+    $profile_object,
     PhabricatorProfilePanel $panel) {
 
     return self::initializeNewBuiltin()
@@ -77,8 +77,7 @@
     return $this->assertAttached($this->panel);
   }
 
-  public function attachProfileObject(
-    PhabricatorProfilePanelInterface $profile_object) {
+  public function attachProfileObject($profile_object) {
     $this->profileObject = $profile_object;
     return $this;
   }