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
@@ -2819,6 +2819,7 @@
     'PhabricatorDivinerApplication' => 'applications/diviner/application/PhabricatorDivinerApplication.php',
     'PhabricatorDocumentEngine' => 'applications/files/document/PhabricatorDocumentEngine.php',
     'PhabricatorDocumentRef' => 'applications/files/document/PhabricatorDocumentRef.php',
+    'PhabricatorDocumentRenderingEngine' => 'applications/files/document/render/PhabricatorDocumentRenderingEngine.php',
     'PhabricatorDoorkeeperApplication' => 'applications/doorkeeper/application/PhabricatorDoorkeeperApplication.php',
     'PhabricatorDraft' => 'applications/draft/storage/PhabricatorDraft.php',
     'PhabricatorDraftDAO' => 'applications/draft/storage/PhabricatorDraftDAO.php',
@@ -3010,6 +3011,7 @@
     'PhabricatorFileDeleteController' => 'applications/files/controller/PhabricatorFileDeleteController.php',
     'PhabricatorFileDeleteTransaction' => 'applications/files/xaction/PhabricatorFileDeleteTransaction.php',
     'PhabricatorFileDocumentController' => 'applications/files/controller/PhabricatorFileDocumentController.php',
+    'PhabricatorFileDocumentRenderingEngine' => 'applications/files/document/render/PhabricatorFileDocumentRenderingEngine.php',
     'PhabricatorFileDropUploadController' => 'applications/files/controller/PhabricatorFileDropUploadController.php',
     'PhabricatorFileEditController' => 'applications/files/controller/PhabricatorFileEditController.php',
     'PhabricatorFileEditEngine' => 'applications/files/editor/PhabricatorFileEditEngine.php',
@@ -8401,6 +8403,7 @@
     'PhabricatorDivinerApplication' => 'PhabricatorApplication',
     'PhabricatorDocumentEngine' => 'Phobject',
     'PhabricatorDocumentRef' => 'Phobject',
+    'PhabricatorDocumentRenderingEngine' => 'Phobject',
     'PhabricatorDoorkeeperApplication' => 'PhabricatorApplication',
     'PhabricatorDraft' => 'PhabricatorDraftDAO',
     'PhabricatorDraftDAO' => 'PhabricatorLiskDAO',
@@ -8624,6 +8627,7 @@
     'PhabricatorFileDeleteController' => 'PhabricatorFileController',
     'PhabricatorFileDeleteTransaction' => 'PhabricatorFileTransactionType',
     'PhabricatorFileDocumentController' => 'PhabricatorFileController',
+    'PhabricatorFileDocumentRenderingEngine' => 'PhabricatorDocumentRenderingEngine',
     'PhabricatorFileDropUploadController' => 'PhabricatorFileController',
     'PhabricatorFileEditController' => 'PhabricatorFileController',
     'PhabricatorFileEditEngine' => 'PhabricatorEditEngine',
diff --git a/src/applications/files/application/PhabricatorFilesApplication.php b/src/applications/files/application/PhabricatorFilesApplication.php
--- a/src/applications/files/application/PhabricatorFilesApplication.php
+++ b/src/applications/files/application/PhabricatorFilesApplication.php
@@ -73,7 +73,7 @@
         => 'PhabricatorFileViewController',
       '/file/' => array(
         '(query/(?P<queryKey>[^/]+)/)?' => 'PhabricatorFileListController',
-        'view/(?P<id>[^/]+)/'.
+        'view/(?P<id>[1-9]\d*)/'.
           '(?:(?P<engineKey>[^/]+)/)?'.
           '(?:\$(?P<lines>\d+(?:-\d+)?))?'
           => 'PhabricatorFileViewController',
diff --git a/src/applications/files/controller/PhabricatorFileDocumentController.php b/src/applications/files/controller/PhabricatorFileDocumentController.php
--- a/src/applications/files/controller/PhabricatorFileDocumentController.php
+++ b/src/applications/files/controller/PhabricatorFileDocumentController.php
@@ -3,10 +3,6 @@
 final class PhabricatorFileDocumentController
   extends PhabricatorFileController {
 
-  private $file;
-  private $engine;
-  private $ref;
-
   public function shouldAllowPublic() {
     return true;
   }
@@ -26,102 +22,14 @@
           'This file ("%s") does not exist or could not be loaded.',
           $file_phid));
     }
-    $this->file = $file;
 
     $ref = id(new PhabricatorDocumentRef())
       ->setFile($file);
-    $this->ref = $ref;
-
-    $engines = PhabricatorDocumentEngine::getEnginesForRef($viewer, $ref);
-    $engine_key = $request->getURIData('engineKey');
-    if (!isset($engines[$engine_key])) {
-      return $this->newErrorResponse(
-        pht(
-          'The engine ("%s") is unknown, or unable to render this document.',
-          $engine_key));
-    }
-    $engine = $engines[$engine_key];
-    $this->engine = $engine;
-
-    $encode_setting = $request->getStr('encode');
-    if (strlen($encode_setting)) {
-      $engine->setEncodingConfiguration($encode_setting);
-    }
-
-    $highlight_setting = $request->getStr('highlight');
-    if (strlen($highlight_setting)) {
-      $engine->setHighlightingConfiguration($highlight_setting);
-    }
-
-    try {
-      $content = $engine->newDocument($ref);
-    } catch (Exception $ex) {
-      return $this->newErrorResponse($ex->getMessage());
-    }
-
-    return $this->newContentResponse($content);
-  }
-
-  private function newErrorResponse($message) {
-    $container = phutil_tag(
-      'div',
-      array(
-        'class' => 'document-engine-error',
-      ),
-      array(
-        id(new PHUIIconView())
-          ->setIcon('fa-exclamation-triangle red'),
-        ' ',
-        $message,
-      ));
-
-    return $this->newContentResponse($container);
-  }
-
-
-  private function newContentResponse($content) {
-    $viewer = $this->getViewer();
-    $request = $this->getRequest();
-
-    $file = $this->file;
-    $engine = $this->engine;
-    $ref = $this->ref;
-
-    if ($request->isAjax()) {
-      return id(new AphrontAjaxResponse())
-        ->setContent(
-          array(
-            'markup' => hsprintf('%s', $content),
-          ));
-    }
-
-    $crumbs = $this->buildApplicationCrumbs();
-    if ($file) {
-      $crumbs->addTextCrumb($file->getMonogram(), $file->getInfoURI());
-    }
-
-    $label = $engine->getViewAsLabel($ref);
-    if ($label) {
-      $crumbs->addTextCrumb($label);
-    }
-
-    $crumbs->setBorder(true);
-
-    $content_frame = id(new PHUIObjectBoxView())
-      ->setBackground(PHUIObjectBoxView::BLUE_PROPERTY)
-      ->appendChild($content);
-
-    $page_frame = id(new PHUITwoColumnView())
-      ->setFooter($content_frame);
 
-    return $this->newPage()
-      ->setCrumbs($crumbs)
-      ->setTitle(
-        array(
-          $ref->getName(),
-          pht('Standalone'),
-        ))
-      ->appendChild($page_frame);
+    return id(new PhabricatorFileDocumentRenderingEngine())
+      ->setRequest($request)
+      ->setController($this)
+      ->newRenderResponse($ref);
   }
 
 }
diff --git a/src/applications/files/controller/PhabricatorFileViewController.php b/src/applications/files/controller/PhabricatorFileViewController.php
--- a/src/applications/files/controller/PhabricatorFileViewController.php
+++ b/src/applications/files/controller/PhabricatorFileViewController.php
@@ -403,122 +403,15 @@
   }
 
   private function newFileContent(PhabricatorFile $file) {
-    $viewer = $this->getViewer();
     $request = $this->getRequest();
 
     $ref = id(new PhabricatorDocumentRef())
       ->setFile($file);
 
-    $engines = PhabricatorDocumentEngine::getEnginesForRef($viewer, $ref);
-
-    $engine_key = $request->getURIData('engineKey');
-    if (!isset($engines[$engine_key])) {
-      $engine_key = head_key($engines);
-    }
-    $engine = $engines[$engine_key];
-
-    $lines = $request->getURILineRange('lines', 1000);
-    if ($lines) {
-      $engine->setHighlightedLines(range($lines[0], $lines[1]));
-    }
-
-    $encode_setting = $request->getStr('encode');
-    if (strlen($encode_setting)) {
-      $engine->setEncodingConfiguration($encode_setting);
-    }
-
-    $highlight_setting = $request->getStr('highlight');
-    if (strlen($highlight_setting)) {
-      $engine->setHighlightingConfiguration($highlight_setting);
-    }
+    $engine = id(new PhabricatorFileDocumentRenderingEngine())
+      ->setRequest($request);
 
-    $views = array();
-    foreach ($engines as $candidate_key => $candidate_engine) {
-      $label = $candidate_engine->getViewAsLabel($ref);
-      if ($label === null) {
-        continue;
-      }
-
-      $view_uri = '/file/view/'.$file->getID().'/'.$candidate_key.'/';
-
-      $view_icon = $candidate_engine->getViewAsIconIcon($ref);
-      $view_color = $candidate_engine->getViewAsIconColor($ref);
-      $loading = $candidate_engine->newLoadingContent($ref);
-
-      $views[] = array(
-        'viewKey' => $candidate_engine->getDocumentEngineKey(),
-        'icon' => $view_icon,
-        'color' => $view_color,
-        'name' => $label,
-        'engineURI' => $candidate_engine->getRenderURI($ref),
-        'viewURI' => $view_uri,
-        'loadingMarkup' => hsprintf('%s', $loading),
-        'canEncode' => $candidate_engine->canConfigureEncoding($ref),
-        'canHighlight' => $candidate_engine->CanConfigureHighlighting($ref),
-      );
-    }
-
-    $viewport_id = celerity_generate_unique_node_id();
-    $control_id = celerity_generate_unique_node_id();
-    $icon = $engine->newDocumentIcon($ref);
-
-    if ($engine->shouldRenderAsync($ref)) {
-      $content = $engine->newLoadingContent($ref);
-      $config = array(
-        'renderControlID' => $control_id,
-      );
-    } else {
-      $content = $engine->newDocument($ref);
-      $config = array();
-    }
-
-    Javelin::initBehavior('document-engine', $config);
-
-    $viewport = phutil_tag(
-      'div',
-      array(
-        'id' => $viewport_id,
-      ),
-      $content);
-
-    $meta = array(
-      'viewportID' => $viewport_id,
-      'viewKey' => $engine->getDocumentEngineKey(),
-      'views' => $views,
-      'standaloneURI' => $engine->getRenderURI($ref),
-      'encode' => array(
-        'icon' => 'fa-font',
-        'name' => pht('Change Text Encoding...'),
-        'uri' => '/services/encoding/',
-        'value' => $encode_setting,
-      ),
-      'highlight' => array(
-        'icon' => 'fa-lightbulb-o',
-        'name' => pht('Highlight As...'),
-        'uri' => '/services/highlight/',
-        'value' => $highlight_setting,
-      ),
-    );
-
-    $view_button = id(new PHUIButtonView())
-      ->setTag('a')
-      ->setText(pht('View Options'))
-      ->setIcon('fa-file-image-o')
-      ->setColor(PHUIButtonView::GREY)
-      ->setID($control_id)
-      ->setMetadata($meta)
-      ->setDropdown(true)
-      ->addSigil('document-engine-view-dropdown');
-
-    $header = id(new PHUIHeaderView())
-      ->setHeaderIcon($icon)
-      ->setHeader($ref->getName())
-      ->addActionLink($view_button);
-
-    return id(new PHUIObjectBoxView())
-      ->setBackground(PHUIObjectBoxView::BLUE_PROPERTY)
-      ->setHeader($header)
-      ->appendChild($viewport);
+    return $engine->newDocumentView($ref);
   }
 
 }
diff --git a/src/applications/files/document/PhabricatorDocumentEngine.php b/src/applications/files/document/PhabricatorDocumentEngine.php
--- a/src/applications/files/document/PhabricatorDocumentEngine.php
+++ b/src/applications/files/document/PhabricatorDocumentEngine.php
@@ -152,18 +152,6 @@
     return null;
   }
 
-  public function getRenderURI(PhabricatorDocumentRef $ref) {
-    $file = $ref->getFile();
-    if (!$file) {
-      throw new PhutilMethodNotImplementedException();
-    }
-
-    $engine_key = $this->getDocumentEngineKey();
-    $file_phid = $file->getPHID();
-
-    return "/file/document/{$engine_key}/{$file_phid}/";
-  }
-
   final public static function getEnginesForRef(
     PhabricatorUser $viewer,
     PhabricatorDocumentRef $ref) {
diff --git a/src/applications/files/document/render/PhabricatorDocumentRenderingEngine.php b/src/applications/files/document/render/PhabricatorDocumentRenderingEngine.php
new file mode 100644
--- /dev/null
+++ b/src/applications/files/document/render/PhabricatorDocumentRenderingEngine.php
@@ -0,0 +1,285 @@
+<?php
+
+abstract class PhabricatorDocumentRenderingEngine
+  extends Phobject {
+
+  private $request;
+  private $controller;
+  private $activeEngine;
+
+  final public function setRequest(AphrontRequest $request) {
+    $this->request = $request;
+    return $this;
+  }
+
+  final public function getRequest() {
+    if (!$this->request) {
+      throw new PhutilInvalidStateException('setRequest');
+    }
+
+    return $this->request;
+  }
+
+  final public function setController(PhabricatorController $controller) {
+    $this->controller = $controller;
+    return $this;
+  }
+
+  final public function getController() {
+    if (!$this->controller) {
+      throw new PhutilInvalidStateException('setController');
+    }
+
+    return $this->controller;
+  }
+
+  final protected function getActiveEngine() {
+    if (!$this->activeEngine) {
+      throw new PhutilInvalidStateException('setActiveEngine');
+    }
+
+    return $this->activeEngine;
+  }
+
+  final public function newDocumentView(PhabricatorDocumentRef $ref) {
+    $request = $this->getRequest();
+    $viewer = $request->getViewer();
+
+    $engines = PhabricatorDocumentEngine::getEnginesForRef($viewer, $ref);
+
+    $engine_key = $this->getSelectedDocumentEngineKey();
+    if (!isset($engines[$engine_key])) {
+      $engine_key = head_key($engines);
+    }
+    $engine = $engines[$engine_key];
+
+    $lines = $request->getURILineRange('lines', 1000);
+    if ($lines) {
+      $engine->setHighlightedLines(range($lines[0], $lines[1]));
+    }
+
+    $encode_setting = $request->getStr('encode');
+    if (strlen($encode_setting)) {
+      $engine->setEncodingConfiguration($encode_setting);
+    }
+
+    $highlight_setting = $request->getStr('highlight');
+    if (strlen($highlight_setting)) {
+      $engine->setHighlightingConfiguration($highlight_setting);
+    }
+
+    $views = array();
+    foreach ($engines as $candidate_key => $candidate_engine) {
+      $label = $candidate_engine->getViewAsLabel($ref);
+      if ($label === null) {
+        continue;
+      }
+
+      $view_uri = $this->newRefViewURI($ref, $candidate_engine);
+
+      $view_icon = $candidate_engine->getViewAsIconIcon($ref);
+      $view_color = $candidate_engine->getViewAsIconColor($ref);
+      $loading = $candidate_engine->newLoadingContent($ref);
+
+      $views[] = array(
+        'viewKey' => $candidate_engine->getDocumentEngineKey(),
+        'icon' => $view_icon,
+        'color' => $view_color,
+        'name' => $label,
+        'engineURI' => $this->newRefRenderURI($ref, $candidate_engine),
+        'viewURI' => $view_uri,
+        'loadingMarkup' => hsprintf('%s', $loading),
+        'canEncode' => $candidate_engine->canConfigureEncoding($ref),
+        'canHighlight' => $candidate_engine->CanConfigureHighlighting($ref),
+      );
+    }
+
+    $viewport_id = celerity_generate_unique_node_id();
+    $control_id = celerity_generate_unique_node_id();
+    $icon = $engine->newDocumentIcon($ref);
+
+    if ($engine->shouldRenderAsync($ref)) {
+      $content = $engine->newLoadingContent($ref);
+      $config = array(
+        'renderControlID' => $control_id,
+      );
+    } else {
+      $content = $engine->newDocument($ref);
+      $config = array();
+    }
+
+    Javelin::initBehavior('document-engine', $config);
+
+    $viewport = phutil_tag(
+      'div',
+      array(
+        'id' => $viewport_id,
+      ),
+      $content);
+
+    $meta = array(
+      'viewportID' => $viewport_id,
+      'viewKey' => $engine->getDocumentEngineKey(),
+      'views' => $views,
+      'encode' => array(
+        'icon' => 'fa-font',
+        'name' => pht('Change Text Encoding...'),
+        'uri' => '/services/encoding/',
+        'value' => $encode_setting,
+      ),
+      'highlight' => array(
+        'icon' => 'fa-lightbulb-o',
+        'name' => pht('Highlight As...'),
+        'uri' => '/services/highlight/',
+        'value' => $highlight_setting,
+      ),
+    );
+
+    $view_button = id(new PHUIButtonView())
+      ->setTag('a')
+      ->setText(pht('View Options'))
+      ->setIcon('fa-file-image-o')
+      ->setColor(PHUIButtonView::GREY)
+      ->setID($control_id)
+      ->setMetadata($meta)
+      ->setDropdown(true)
+      ->addSigil('document-engine-view-dropdown');
+
+    $header = id(new PHUIHeaderView())
+      ->setHeaderIcon($icon)
+      ->setHeader($ref->getName())
+      ->addActionLink($view_button);
+
+    return id(new PHUIObjectBoxView())
+      ->setBackground(PHUIObjectBoxView::BLUE_PROPERTY)
+      ->setHeader($header)
+      ->appendChild($viewport);
+  }
+
+  abstract protected function newRefViewURI(
+    PhabricatorDocumentRef $ref,
+    PhabricatorDocumentEngine $engine);
+
+  abstract protected function newRefRenderURI(
+    PhabricatorDocumentRef $ref,
+    PhabricatorDocumentEngine $engine);
+
+  protected function getSelectedDocumentEngineKey() {
+    return $this->getRequest()->getURIData('engineKey');
+  }
+
+  final public function newRenderResponse(PhabricatorDocumentRef $ref) {
+    $request = $this->getRequest();
+    $viewer = $request->getViewer();
+
+    $engines = PhabricatorDocumentEngine::getEnginesForRef($viewer, $ref);
+    $engine_key = $request->getURIData('engineKey');
+    if (!isset($engines[$engine_key])) {
+      return $this->newErrorResponse(
+        $ref,
+        pht(
+          'The engine ("%s") is unknown, or unable to render this document.',
+          $engine_key));
+    }
+    $engine = $engines[$engine_key];
+
+    $this->activeEngine = $engine;
+
+    $encode_setting = $request->getStr('encode');
+    if (strlen($encode_setting)) {
+      $engine->setEncodingConfiguration($encode_setting);
+    }
+
+    $highlight_setting = $request->getStr('highlight');
+    if (strlen($highlight_setting)) {
+      $engine->setHighlightingConfiguration($highlight_setting);
+    }
+
+    try {
+      $content = $engine->newDocument($ref);
+    } catch (Exception $ex) {
+      return $this->newErrorResponse($ref, $ex->getMessage());
+    }
+
+    return $this->newContentResponse($ref, $content);
+  }
+
+  private function newErrorResponse(
+    PhabricatorDocumentRef $ref,
+    $message) {
+
+    $container = phutil_tag(
+      'div',
+      array(
+        'class' => 'document-engine-error',
+      ),
+      array(
+        id(new PHUIIconView())
+          ->setIcon('fa-exclamation-triangle red'),
+        ' ',
+        $message,
+      ));
+
+    return $this->newContentResponse($ref, $container);
+  }
+
+  private function newContentResponse(
+    PhabricatorDocumentRef $ref,
+    $content) {
+
+    $request = $this->getRequest();
+    $viewer = $request->getViewer();
+    $controller = $this->getController();
+
+    if ($request->isAjax()) {
+      return id(new AphrontAjaxResponse())
+        ->setContent(
+          array(
+            'markup' => hsprintf('%s', $content),
+          ));
+    }
+
+    $crumbs = $this->newCrumbs($ref);
+    if ($crumbs) {
+      $crumbs->setBorder(true);
+    }
+
+    $content_frame = id(new PHUIObjectBoxView())
+      ->setBackground(PHUIObjectBoxView::BLUE_PROPERTY)
+      ->appendChild($content);
+
+    $page_frame = id(new PHUITwoColumnView())
+      ->setFooter($content_frame);
+
+    return $controller->newPage()
+      ->setCrumbs($crumbs)
+      ->setTitle(
+        array(
+          $ref->getName(),
+          pht('Standalone'),
+        ))
+      ->appendChild($page_frame);
+  }
+
+  protected function newCrumbs(PhabricatorDocumentRef $ref) {
+    $controller = $this->getController();
+    $crumbs = $controller->buildApplicationCrumbsForEditEngine();
+
+    $this->addApplicationCrumbs($ref, $crumbs);
+
+    $engine = $this->getActiveEngine();
+    $label = $engine->getViewAsLabel($ref);
+    if ($label) {
+      $crumbs->addTextCrumb($label);
+    }
+
+    return $crumbs;
+  }
+
+  protected function addApplicationCrumbs(
+    PhabricatorDocumentRef $ref,
+    PHUICrumbsView $crumbs) {
+    return;
+  }
+
+}
diff --git a/src/applications/files/document/render/PhabricatorFileDocumentRenderingEngine.php b/src/applications/files/document/render/PhabricatorFileDocumentRenderingEngine.php
new file mode 100644
--- /dev/null
+++ b/src/applications/files/document/render/PhabricatorFileDocumentRenderingEngine.php
@@ -0,0 +1,47 @@
+<?php
+
+final class PhabricatorFileDocumentRenderingEngine
+  extends PhabricatorDocumentRenderingEngine {
+
+  protected function newRefViewURI(
+    PhabricatorDocumentRef $ref,
+    PhabricatorDocumentEngine $engine) {
+
+    $file = $ref->getFile();
+    $engine_key = $engine->getDocumentEngineKey();
+
+    return urisprintf(
+      '/file/view/%d/%s/',
+      $file->getID(),
+      $engine_key);
+  }
+
+  protected function newRefRenderURI(
+    PhabricatorDocumentRef $ref,
+    PhabricatorDocumentEngine $engine) {
+    $file = $ref->getFile();
+    if (!$file) {
+      throw new PhutilMethodNotImplementedException();
+    }
+
+    $engine_key = $engine->getDocumentEngineKey();
+    $file_phid = $file->getPHID();
+
+    return urisprintf(
+      '/file/document/%s/%s/',
+      $engine_key,
+      $file_phid);
+  }
+
+  protected function addApplicationCrumbs(
+    PhabricatorDocumentRef $ref,
+    PHUICrumbsView $crumbs) {
+
+    $file = $ref->getFile();
+    if ($file) {
+      $crumbs->addTextCrumb($file->getMonogram(), $file->getInfoURI());
+    }
+
+  }
+
+}