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
@@ -136,6 +136,7 @@
     'AphrontFormView' => 'view/form/AphrontFormView.php',
     'AphrontGlyphBarView' => 'view/widget/bars/AphrontGlyphBarView.php',
     'AphrontHTMLResponse' => 'aphront/response/AphrontHTMLResponse.php',
+    'AphrontHTTPProxyResponse' => 'aphront/response/AphrontHTTPProxyResponse.php',
     'AphrontHTTPSink' => 'aphront/sink/AphrontHTTPSink.php',
     'AphrontHTTPSinkTestCase' => 'aphront/sink/__tests__/AphrontHTTPSinkTestCase.php',
     'AphrontIsolatedDatabaseConnectionTestCase' => 'infrastructure/storage/__tests__/AphrontIsolatedDatabaseConnectionTestCase.php',
@@ -3240,6 +3241,7 @@
     'AphrontFormView' => 'AphrontView',
     'AphrontGlyphBarView' => 'AphrontBarView',
     'AphrontHTMLResponse' => 'AphrontResponse',
+    'AphrontHTTPProxyResponse' => 'AphrontResponse',
     'AphrontHTTPSinkTestCase' => 'PhabricatorTestCase',
     'AphrontIsolatedDatabaseConnectionTestCase' => 'PhabricatorTestCase',
     'AphrontIsolatedHTTPSink' => 'AphrontHTTPSink',
diff --git a/src/aphront/response/AphrontHTTPProxyResponse.php b/src/aphront/response/AphrontHTTPProxyResponse.php
new file mode 100644
--- /dev/null
+++ b/src/aphront/response/AphrontHTTPProxyResponse.php
@@ -0,0 +1,65 @@
+<?php
+
+/**
+ * Responds to a request by proxying an HTTP future.
+ *
+ * NOTE: This is currently very inefficient for large responses, and buffers
+ * the entire response into memory before returning it. It should be updated
+ * to stream the response instead, but we need to complete additional
+ * infrastructure work first.
+ */
+final class AphrontHTTPProxyResponse extends AphrontResponse {
+
+  private $future;
+  private $headers;
+  private $httpCode;
+
+  public function setHTTPFuture(HTTPSFuture $future) {
+    $this->future = $future;
+    return $this;
+  }
+
+  public function getHTTPFuture() {
+    return $this->future;
+  }
+
+  public function getCacheHeaders() {
+    return array();
+  }
+
+  public function getHeaders() {
+    $this->readRequestHeaders();
+    return array_merge(
+      parent::getHeaders(),
+      $this->headers,
+      array(
+        array('X-Phabricator-Proxy', 'true'),
+      ));
+  }
+
+  public function buildResponseString() {
+    // TODO: AphrontResponse needs to support streaming responses.
+    return $this->readRequest();
+  }
+
+  public function getHTTPResponseCode() {
+    $this->readRequestHeaders();
+    return $this->httpCode;
+  }
+
+  private function readRequestHeaders() {
+    // TODO: This should read only the headers.
+    $this->readRequest();
+  }
+
+  private function readRequest() {
+    // TODO: This is grossly inefficient for large requests.
+
+    list($status, $body, $headers) = $this->future->resolve();
+    $this->httpCode = $status->getStatusCode();
+    $this->headers = $headers;
+
+    return $body;
+  }
+
+}