diff --git a/conf/default.conf.php b/conf/default.conf.php
index 2d5f697122..fb23e659f8 100644
--- a/conf/default.conf.php
+++ b/conf/default.conf.php
@@ -645,6 +645,7 @@ return array(
     'image/png'   => 'image/png',
     'image/gif'   => 'image/gif',
     'text/plain'  => 'text/plain; charset=utf-8',
+    'text/x-diff' => 'text/plain; charset=utf-8',
 
     // ".ico" favicon files, which have mime type diversity. See:
     // http://en.wikipedia.org/wiki/ICO_(file_format)#MIME_type
diff --git a/src/__phutil_library_map__.php b/src/__phutil_library_map__.php
index dfd985b953..52f8772e47 100644
--- a/src/__phutil_library_map__.php
+++ b/src/__phutil_library_map__.php
@@ -325,6 +325,7 @@ phutil_register_library_map(array(
     'DiffusionGitHistoryQuery' => 'applications/diffusion/query/history/git',
     'DiffusionGitLastModifiedQuery' => 'applications/diffusion/query/lastmodified/git',
     'DiffusionGitMergedCommitsQuery' => 'applications/diffusion/query/mergedcommits/git',
+    'DiffusionGitRawDiffQuery' => 'applications/diffusion/query/rawdiff/git',
     'DiffusionGitRenameHistoryQuery' => 'applications/diffusion/query/renamehistory/git',
     'DiffusionGitRequest' => 'applications/diffusion/request/git',
     'DiffusionGitTagListQuery' => 'applications/diffusion/query/taglist/git',
@@ -345,6 +346,7 @@ phutil_register_library_map(array(
     'DiffusionMercurialHistoryQuery' => 'applications/diffusion/query/history/mercurial',
     'DiffusionMercurialLastModifiedQuery' => 'applications/diffusion/query/lastmodified/mercurial',
     'DiffusionMercurialMergedCommitsQuery' => 'applications/diffusion/query/mergedcommits/mercurial',
+    'DiffusionMercurialRawDiffQuery' => 'applications/diffusion/query/rawdiff/mercurial',
     'DiffusionMercurialRenameHistoryQuery' => 'applications/diffusion/query/renamehistory/mercurial',
     'DiffusionMercurialRequest' => 'applications/diffusion/request/mercurial',
     'DiffusionMercurialTagListQuery' => 'applications/diffusion/query/taglist/mercurial',
@@ -357,6 +359,7 @@ phutil_register_library_map(array(
     'DiffusionPathQueryTestCase' => 'applications/diffusion/query/pathid/base/__tests__',
     'DiffusionPathValidateController' => 'applications/diffusion/controller/pathvalidate',
     'DiffusionQuery' => 'applications/diffusion/query/base',
+    'DiffusionRawDiffQuery' => 'applications/diffusion/query/rawdiff/base',
     'DiffusionRenameHistoryQuery' => 'applications/diffusion/query/renamehistory/base',
     'DiffusionRepositoryController' => 'applications/diffusion/controller/repository',
     'DiffusionRepositoryPath' => 'applications/diffusion/data/repositorypath',
@@ -371,6 +374,7 @@ phutil_register_library_map(array(
     'DiffusionSvnHistoryQuery' => 'applications/diffusion/query/history/svn',
     'DiffusionSvnLastModifiedQuery' => 'applications/diffusion/query/lastmodified/svn',
     'DiffusionSvnMergedCommitsQuery' => 'applications/diffusion/query/mergedcommits/svn',
+    'DiffusionSvnRawDiffQuery' => 'applications/diffusion/query/rawdiff/svn',
     'DiffusionSvnRenameHistoryQuery' => 'applications/diffusion/query/renamehistory/svn',
     'DiffusionSvnRequest' => 'applications/diffusion/request/svn',
     'DiffusionSvnTagListQuery' => 'applications/diffusion/query/taglist/svn',
@@ -1301,6 +1305,7 @@ phutil_register_library_map(array(
     'DiffusionGitHistoryQuery' => 'DiffusionHistoryQuery',
     'DiffusionGitLastModifiedQuery' => 'DiffusionLastModifiedQuery',
     'DiffusionGitMergedCommitsQuery' => 'DiffusionMergedCommitsQuery',
+    'DiffusionGitRawDiffQuery' => 'DiffusionRawDiffQuery',
     'DiffusionGitRenameHistoryQuery' => 'DiffusionRenameHistoryQuery',
     'DiffusionGitRequest' => 'DiffusionRequest',
     'DiffusionGitTagListQuery' => 'DiffusionTagListQuery',
@@ -1321,6 +1326,7 @@ phutil_register_library_map(array(
     'DiffusionMercurialHistoryQuery' => 'DiffusionHistoryQuery',
     'DiffusionMercurialLastModifiedQuery' => 'DiffusionLastModifiedQuery',
     'DiffusionMercurialMergedCommitsQuery' => 'DiffusionMergedCommitsQuery',
+    'DiffusionMercurialRawDiffQuery' => 'DiffusionRawDiffQuery',
     'DiffusionMercurialRenameHistoryQuery' => 'DiffusionRenameHistoryQuery',
     'DiffusionMercurialRequest' => 'DiffusionRequest',
     'DiffusionMercurialTagListQuery' => 'DiffusionTagListQuery',
@@ -1328,6 +1334,7 @@ phutil_register_library_map(array(
     'DiffusionPathCompleteController' => 'DiffusionController',
     'DiffusionPathQueryTestCase' => 'PhabricatorTestCase',
     'DiffusionPathValidateController' => 'DiffusionController',
+    'DiffusionRawDiffQuery' => 'DiffusionQuery',
     'DiffusionRenameHistoryQuery' => 'DiffusionQuery',
     'DiffusionRepositoryController' => 'DiffusionController',
     'DiffusionSvnBrowseQuery' => 'DiffusionBrowseQuery',
@@ -1339,6 +1346,7 @@ phutil_register_library_map(array(
     'DiffusionSvnHistoryQuery' => 'DiffusionHistoryQuery',
     'DiffusionSvnLastModifiedQuery' => 'DiffusionLastModifiedQuery',
     'DiffusionSvnMergedCommitsQuery' => 'DiffusionMergedCommitsQuery',
+    'DiffusionSvnRawDiffQuery' => 'DiffusionRawDiffQuery',
     'DiffusionSvnRenameHistoryQuery' => 'DiffusionRenameHistoryQuery',
     'DiffusionSvnRequest' => 'DiffusionRequest',
     'DiffusionSvnTagListQuery' => 'DiffusionTagListQuery',
diff --git a/src/applications/diffusion/controller/commit/DiffusionCommitController.php b/src/applications/diffusion/controller/commit/DiffusionCommitController.php
index b9346efb64..ec3afefaae 100644
--- a/src/applications/diffusion/controller/commit/DiffusionCommitController.php
+++ b/src/applications/diffusion/controller/commit/DiffusionCommitController.php
@@ -34,6 +34,10 @@ final class DiffusionCommitController extends DiffusionController {
     $request = $this->getRequest();
     $user = $request->getUser();
 
+    if ($request->getStr('diff')) {
+      return $this->buildRawDiffResponse($drequest);
+    }
+
     $callsign = $drequest->getRepository()->getCallsign();
 
     $content = array();
@@ -676,7 +680,8 @@ final class DiffusionCommitController extends DiffusionController {
   private function renderHeadsupActionList(
     PhabricatorRepositoryCommit $commit) {
 
-    $user = $this->getRequest()->getUser();
+    $request = $this->getRequest();
+    $user = $request->getUser();
 
     $actions = array();
 
@@ -725,6 +730,12 @@ final class DiffusionCommitController extends DiffusionController {
     $action->setClass('transcripts-herald');
     $actions[] = $action;
 
+    $action = new AphrontHeadsupActionView();
+    $action->setName('Download Raw Diff');
+    $action->setURI($request->getRequestURI()->alter('diff', true));
+    $action->setClass('action-download');
+    $actions[] = $action;
+
     $action_list = new AphrontHeadsupActionListView();
     $action_list->setActions($actions);
 
@@ -795,4 +806,29 @@ final class DiffusionCommitController extends DiffusionController {
     return trim($stdout, "() \n");
   }
 
+  private function buildRawDiffResponse(DiffusionRequest $drequest) {
+    $raw_query = DiffusionRawDiffQuery::newFromDiffusionRequest($drequest);
+    $raw_diff  = $raw_query->loadRawDiff();
+
+    $hash = PhabricatorHash::digest($raw_diff);
+
+    $file = id(new PhabricatorFile())->loadOneWhere(
+      'contentHash = %s LIMIT 1',
+      $hash);
+    if (!$file) {
+      // We're just caching the data; this is always safe.
+      $unguarded = AphrontWriteGuard::beginScopedUnguardedWrites();
+
+      $file = PhabricatorFile::newFromFileData(
+        $raw_diff,
+        array(
+          'name' => $drequest->getCommit().'.diff',
+        ));
+
+      unset($unguarded);
+    }
+
+    return id(new AphrontRedirectResponse())->setURI($file->getBestURI());
+  }
+
 }
diff --git a/src/applications/diffusion/controller/commit/__init__.php b/src/applications/diffusion/controller/commit/__init__.php
index 75743da859..03fb3bdd9e 100644
--- a/src/applications/diffusion/controller/commit/__init__.php
+++ b/src/applications/diffusion/controller/commit/__init__.php
@@ -6,6 +6,8 @@
 
 
 
+phutil_require_module('phabricator', 'aphront/response/redirect');
+phutil_require_module('phabricator', 'aphront/writeguard');
 phutil_require_module('phabricator', 'applications/audit/constants/action');
 phutil_require_module('phabricator', 'applications/audit/constants/commitstatus');
 phutil_require_module('phabricator', 'applications/audit/constants/status');
@@ -25,11 +27,13 @@ phutil_require_module('phabricator', 'applications/diffusion/query/parents/base'
 phutil_require_module('phabricator', 'applications/diffusion/query/path');
 phutil_require_module('phabricator', 'applications/diffusion/query/pathchange/base');
 phutil_require_module('phabricator', 'applications/diffusion/query/pathid/base');
+phutil_require_module('phabricator', 'applications/diffusion/query/rawdiff/base');
 phutil_require_module('phabricator', 'applications/diffusion/request/base');
 phutil_require_module('phabricator', 'applications/diffusion/view/commentlist');
 phutil_require_module('phabricator', 'applications/diffusion/view/commitchangetable');
 phutil_require_module('phabricator', 'applications/diffusion/view/historytable');
 phutil_require_module('phabricator', 'applications/draft/storage/draft');
+phutil_require_module('phabricator', 'applications/files/storage/file');
 phutil_require_module('phabricator', 'applications/flag/constants/color');
 phutil_require_module('phabricator', 'applications/flag/query/flag');
 phutil_require_module('phabricator', 'applications/markup/engine');
@@ -41,6 +45,7 @@ phutil_require_module('phabricator', 'infrastructure/edges/constants/config');
 phutil_require_module('phabricator', 'infrastructure/edges/query/edge');
 phutil_require_module('phabricator', 'infrastructure/env');
 phutil_require_module('phabricator', 'infrastructure/javelin/api');
+phutil_require_module('phabricator', 'infrastructure/util/hash');
 phutil_require_module('phabricator', 'storage/queryfx');
 phutil_require_module('phabricator', 'view/form/base');
 phutil_require_module('phabricator', 'view/form/control/select');
diff --git a/src/applications/diffusion/query/diff/git/DiffusionGitDiffQuery.php b/src/applications/diffusion/query/diff/git/DiffusionGitDiffQuery.php
index b7a34f4d83..550d1c96b7 100644
--- a/src/applications/diffusion/query/diff/git/DiffusionGitDiffQuery.php
+++ b/src/applications/diffusion/query/diff/git/DiffusionGitDiffQuery.php
@@ -29,44 +29,8 @@ final class DiffusionGitDiffQuery extends DiffusionDiffQuery {
     // TODO: This side effect is kind of skethcy.
     $drequest->setCommit($effective_commit);
 
-    $options = array(
-      '-M',
-      '-C',
-      '--no-ext-diff',
-      '--no-color',
-      '--src-prefix=a/',
-      '--dst-prefix=b/',
-      '-U65535',
-    );
-    $options = implode(' ', $options);
-
-    try {
-      list($raw_diff) = $repository->execxLocalCommand(
-        'diff %C %s^ %s -- %s',
-        $options,
-        $effective_commit,
-        $effective_commit,
-        $drequest->getPath());
-    } catch (CommandException $ex) {
-      // Check if this is the root commit by seeing if it has parents.
-      list($parents) = $repository->execxLocalCommand(
-        'log --format=%s %s --',
-        '%P', // "parents"
-        $effective_commit);
-      if (!strlen(trim($parents))) {
-        // No parents means we're looking at the root revision. Diff against
-        // the empty tree hash instead, since there is no parent so "^" does
-        // not work. See ArcanistGitAPI for more discussion.
-        list($raw_diff) = $repository->execxLocalCommand(
-          'diff %C %s %s -- %s',
-          $options,
-          ArcanistGitAPI::GIT_MAGIC_ROOT_COMMIT,
-          $effective_commit,
-          $drequest->getPath());
-      } else {
-        throw $ex;
-      }
-    }
+    $raw_query = DiffusionRawDiffQuery::newFromDiffusionRequest($drequest);
+    $raw_diff = $raw_query->loadRawDiff();
 
     if (!$raw_diff) {
       return null;
diff --git a/src/applications/diffusion/query/diff/git/__init__.php b/src/applications/diffusion/query/diff/git/__init__.php
index 766d74997d..2550760944 100644
--- a/src/applications/diffusion/query/diff/git/__init__.php
+++ b/src/applications/diffusion/query/diff/git/__init__.php
@@ -7,10 +7,10 @@
 
 
 phutil_require_module('arcanist', 'parser/diff');
-phutil_require_module('arcanist', 'repository/api/git');
 
 phutil_require_module('phabricator', 'applications/differential/storage/diff');
 phutil_require_module('phabricator', 'applications/diffusion/query/diff/base');
+phutil_require_module('phabricator', 'applications/diffusion/query/rawdiff/base');
 
 
 phutil_require_source('DiffusionGitDiffQuery.php');
diff --git a/src/applications/diffusion/query/diff/mercurial/DiffusionMercurialDiffQuery.php b/src/applications/diffusion/query/diff/mercurial/DiffusionMercurialDiffQuery.php
index 7cfe68e988..d6525e95fb 100644
--- a/src/applications/diffusion/query/diff/mercurial/DiffusionMercurialDiffQuery.php
+++ b/src/applications/diffusion/query/diff/mercurial/DiffusionMercurialDiffQuery.php
@@ -29,13 +29,8 @@ final class DiffusionMercurialDiffQuery extends DiffusionDiffQuery {
     // TODO: This side effect is kind of skethcy.
     $drequest->setCommit($effective_commit);
 
-    $path = $drequest->getPath();
-
-    list($raw_diff) = $repository->execxLocalCommand(
-      'diff -U %d --git --change %s -- %s',
-      65535,
-      $effective_commit,
-      $path);
+    $query = DiffusionRawDiffQuery::newFromDiffusionRequest($drequest);
+    $raw_diff = $query->loadRawDiff();
 
     $parser = new ArcanistDiffParser();
 
diff --git a/src/applications/diffusion/query/diff/mercurial/__init__.php b/src/applications/diffusion/query/diff/mercurial/__init__.php
index 8daa080d53..e28ac04e6b 100644
--- a/src/applications/diffusion/query/diff/mercurial/__init__.php
+++ b/src/applications/diffusion/query/diff/mercurial/__init__.php
@@ -10,6 +10,7 @@ phutil_require_module('arcanist', 'parser/diff');
 
 phutil_require_module('phabricator', 'applications/differential/storage/diff');
 phutil_require_module('phabricator', 'applications/diffusion/query/diff/base');
+phutil_require_module('phabricator', 'applications/diffusion/query/rawdiff/base');
 
 
 phutil_require_source('DiffusionMercurialDiffQuery.php');
diff --git a/src/applications/diffusion/query/rawdiff/base/DiffusionRawDiffQuery.php b/src/applications/diffusion/query/rawdiff/base/DiffusionRawDiffQuery.php
new file mode 100644
index 0000000000..d9eab546ea
--- /dev/null
+++ b/src/applications/diffusion/query/rawdiff/base/DiffusionRawDiffQuery.php
@@ -0,0 +1,52 @@
+<?php
+
+/*
+ * Copyright 2012 Facebook, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+abstract class DiffusionRawDiffQuery extends DiffusionQuery {
+
+  private $request;
+  private $timeout;
+  private $linesOfContext = 65535;
+
+  final public static function newFromDiffusionRequest(
+    DiffusionRequest $request) {
+    return parent::newQueryObject(__CLASS__, $request);
+  }
+
+  final public function loadRawDiff() {
+    return $this->executeQuery();
+  }
+
+  final public function setTimeout($timeout) {
+    $this->timeout = $timeout;
+    return $this;
+  }
+
+  final public function getTimeout() {
+    return $this->timeout;
+  }
+
+  final public function setLinesOfContext($lines_of_context) {
+    $this->linesOfContext = $lines_of_context;
+    return $this;
+  }
+
+  final public function getLinesOfContext() {
+    return $this->linesOfContext;
+  }
+
+}
diff --git a/src/applications/diffusion/query/rawdiff/base/__init__.php b/src/applications/diffusion/query/rawdiff/base/__init__.php
new file mode 100644
index 0000000000..3d228bac08
--- /dev/null
+++ b/src/applications/diffusion/query/rawdiff/base/__init__.php
@@ -0,0 +1,12 @@
+<?php
+/**
+ * This file is automatically generated. Lint this module to rebuild it.
+ * @generated
+ */
+
+
+
+phutil_require_module('phabricator', 'applications/diffusion/query/base');
+
+
+phutil_require_source('DiffusionRawDiffQuery.php');
diff --git a/src/applications/diffusion/query/rawdiff/git/DiffusionGitRawDiffQuery.php b/src/applications/diffusion/query/rawdiff/git/DiffusionGitRawDiffQuery.php
new file mode 100644
index 0000000000..c964b01891
--- /dev/null
+++ b/src/applications/diffusion/query/rawdiff/git/DiffusionGitRawDiffQuery.php
@@ -0,0 +1,85 @@
+<?php
+
+/*
+ * Copyright 2012 Facebook, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+final class DiffusionGitRawDiffQuery extends DiffusionRawDiffQuery {
+
+  protected function executeQuery() {
+    $drequest = $this->getRequest();
+    $repository = $drequest->getRepository();
+
+    $commit = $drequest->getCommit();
+
+    $options = array(
+      '-M',
+      '-C',
+      '--no-ext-diff',
+      '--no-color',
+      '--src-prefix=a/',
+      '--dst-prefix=b/',
+      '-U'.(int)$this->getLinesOfContext(),
+    );
+    $options = implode(' ', $options);
+
+    // If there's no path, get the entire raw diff.
+    $path = nonempty($drequest->getPath(), '.');
+
+    $future = $repository->getLocalCommandFuture(
+      "diff %C %s^ %s -- %s",
+      $options,
+      $commit,
+      $commit,
+      $path);
+
+    if ($this->getTimeout()) {
+      $future->setTimeout($this->getTimeout());
+    }
+
+    try {
+      list($raw_diff) = $future->resolvex();
+    } catch (CommandException $ex) {
+      // Check if this is the root commit by seeing if it has parents.
+      list($parents) = $repository->execxLocalCommand(
+        'log --format=%s %s --',
+        '%P', // "parents"
+        $effective_commit);
+
+      if (strlen(trim($parents))) {
+        throw $ex;
+      }
+
+      // No parents means we're looking at the root revision. Diff against
+      // the empty tree hash instead, since there is no parent so "^" does
+      // not work. See ArcanistGitAPI for more discussion.
+      $future = $repository->getLocalCommandFuture(
+        'diff %C %s %s -- %s',
+        $options,
+        ArcanistGitAPI::GIT_MAGIC_ROOT_COMMIT,
+        $commit,
+        $drequest->getPath());
+
+      if ($this->getTimeout()) {
+        $future->setTimeout($this->getTimeout());
+      }
+
+      list($raw_diff) = $future->resolvex();
+    }
+
+    return $raw_diff;
+  }
+
+}
diff --git a/src/applications/diffusion/query/rawdiff/git/__init__.php b/src/applications/diffusion/query/rawdiff/git/__init__.php
new file mode 100644
index 0000000000..e619a17d62
--- /dev/null
+++ b/src/applications/diffusion/query/rawdiff/git/__init__.php
@@ -0,0 +1,16 @@
+<?php
+/**
+ * This file is automatically generated. Lint this module to rebuild it.
+ * @generated
+ */
+
+
+
+phutil_require_module('arcanist', 'repository/api/git');
+
+phutil_require_module('phabricator', 'applications/diffusion/query/rawdiff/base');
+
+phutil_require_module('phutil', 'utils');
+
+
+phutil_require_source('DiffusionGitRawDiffQuery.php');
diff --git a/src/applications/diffusion/query/rawdiff/mercurial/DiffusionMercurialRawDiffQuery.php b/src/applications/diffusion/query/rawdiff/mercurial/DiffusionMercurialRawDiffQuery.php
new file mode 100644
index 0000000000..9551a1904c
--- /dev/null
+++ b/src/applications/diffusion/query/rawdiff/mercurial/DiffusionMercurialRawDiffQuery.php
@@ -0,0 +1,45 @@
+<?php
+
+/*
+ * Copyright 2012 Facebook, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+final class DiffusionMercurialRawDiffQuery extends DiffusionRawDiffQuery {
+
+  protected function executeQuery() {
+    $drequest = $this->getRequest();
+    $repository = $drequest->getRepository();
+
+    $commit = $drequest->getCommit();
+
+    // If there's no path, get the entire raw diff.
+    $path = nonempty($drequest->getPath(), '.');
+
+    $future = $repository->getLocalCommandFuture(
+      'diff -U %d --git --change %s -- %s',
+      $this->getLinesOfContext(),
+      $commit,
+      $path);
+
+    if ($this->getTimeout()) {
+      $future->setTimeout($this->getTimeout());
+    }
+
+    list($raw_diff) = $future->resolvex();
+
+    return $raw_diff;
+  }
+
+}
diff --git a/src/applications/diffusion/query/rawdiff/mercurial/__init__.php b/src/applications/diffusion/query/rawdiff/mercurial/__init__.php
new file mode 100644
index 0000000000..0151f1d2d0
--- /dev/null
+++ b/src/applications/diffusion/query/rawdiff/mercurial/__init__.php
@@ -0,0 +1,14 @@
+<?php
+/**
+ * This file is automatically generated. Lint this module to rebuild it.
+ * @generated
+ */
+
+
+
+phutil_require_module('phabricator', 'applications/diffusion/query/rawdiff/base');
+
+phutil_require_module('phutil', 'utils');
+
+
+phutil_require_source('DiffusionMercurialRawDiffQuery.php');
diff --git a/src/applications/diffusion/query/rawdiff/svn/DiffusionSvnRawDiffQuery.php b/src/applications/diffusion/query/rawdiff/svn/DiffusionSvnRawDiffQuery.php
new file mode 100644
index 0000000000..39d81d9635
--- /dev/null
+++ b/src/applications/diffusion/query/rawdiff/svn/DiffusionSvnRawDiffQuery.php
@@ -0,0 +1,42 @@
+<?php
+
+/*
+ * Copyright 2012 Facebook, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+final class DiffusionSvnRawDiffQuery extends DiffusionRawDiffQuery {
+
+  protected function executeQuery() {
+    $drequest = $this->getRequest();
+    $repository = $drequest->getRepository();
+
+    $commit = $drequest->getCommit();
+
+    $future = $repository->getRemoteCommandFuture(
+      'diff --diff-cmd diff -x -U%d -c %d %s%s@',
+      $this->getLinesOfContext(),
+      $commit,
+      $repository->getRemoteURI(),
+      $drequest->getPath());
+
+    if ($this->getTimeout()) {
+      $future->setTimeout($this->getTimeout());
+    }
+
+    list($raw_diff) = $future->resolvex();
+    return $raw_diff;
+  }
+
+}
diff --git a/src/applications/diffusion/query/rawdiff/svn/__init__.php b/src/applications/diffusion/query/rawdiff/svn/__init__.php
new file mode 100644
index 0000000000..f17276965c
--- /dev/null
+++ b/src/applications/diffusion/query/rawdiff/svn/__init__.php
@@ -0,0 +1,12 @@
+<?php
+/**
+ * This file is automatically generated. Lint this module to rebuild it.
+ * @generated
+ */
+
+
+
+phutil_require_module('phabricator', 'applications/diffusion/query/rawdiff/base');
+
+
+phutil_require_source('DiffusionSvnRawDiffQuery.php');
diff --git a/webroot/rsrc/css/aphront/headsup-action-list-view.css b/webroot/rsrc/css/aphront/headsup-action-list-view.css
index 5662226e04..302bda1e6d 100644
--- a/webroot/rsrc/css/aphront/headsup-action-list-view.css
+++ b/webroot/rsrc/css/aphront/headsup-action-list-view.css
@@ -54,6 +54,10 @@
   background-image: url(/rsrc/image/icon/tango/upload.png);
 }
 
+.aphront-headsup-action-list .action-download {
+  background-image: url(/rsrc/image/icon/tango/go-down.png);
+}
+
 .aphront-headsup-action-list .transcripts-metamta {
   background-image: url(/rsrc/image/icon/tango/log.png);
 }
diff --git a/webroot/rsrc/image/icon/tango/go-down.png b/webroot/rsrc/image/icon/tango/go-down.png
new file mode 100644
index 0000000000..3dd7fccdf0
Binary files /dev/null and b/webroot/rsrc/image/icon/tango/go-down.png differ