diff --git a/Dockerfile b/Dockerfile
index a436a17..5b859ed 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,38 +1,40 @@
 FROM mozilla/mozphab:37bf10d57c773185202ce6d755cfd8f1cbbcad67
 
 COPY extensions /app/moz-extensions
 
 # Move static resources to phabricator, add files to celerity map array
 COPY extensions/src/motd/css/MozillaMOTD.css /app/phabricator/webroot/rsrc/css/MozillaMOTD.css
 COPY extensions/src/auth/PhabricatorBMOAuth.css /app/phabricator/webroot/rsrc/css/PhabricatorBMOAuth.css
 COPY extensions/src/auth/PhabricatorBMOAuth.js /app/phabricator/webroot/rsrc/js/PhabricatorBMOAuth.js
 
 USER root
 
 # Install dependencies
 ENV COMPOSER_ALLOW_SUPERUSER 1
 ENV COMPOSER_VENDOR_DIR /app/phabricator/externals/extensions
 RUN \
     curl -sS https://getcomposer.org/installer | php && \
     php composer.phar require --no-plugins --no-scripts "sentry/sentry"
 
 # Apply customization patches
 COPY patches /app/patches
 RUN \
     cd /app/phabricator && \
     for i in /app/patches/phabricator/*.patch; do patch -p1 < $i; done
 
 # Configure Phabricator to use moz-extensions library
 RUN \
     mkdir /app/phabricator/conf/custom/ && \
     echo custom/moz-extensions > /app/phabricator/conf/local/ENVIRONMENT
 COPY moz-extensions.conf.php /app/phabricator/conf/custom/
 
 # Update build_url in version.json
 COPY phabext.json /app
 COPY update_build_url.py /app
 RUN /app/update_build_url.py
 
 RUN chown -R app:app /app
+RUN chmod +x /app/moz-extensions/bin/*
+
 USER app
 VOLUME ["/app"]
diff --git a/extensions/bin/config_dump b/extensions/bin/config_dump
new file mode 100644
index 0000000..8b8acf3
--- /dev/null
+++ b/extensions/bin/config_dump
@@ -0,0 +1,42 @@
+#!/usr/bin/env php
+<?php
+
+/**
+ * Dump the customized config keys with values to a JSON file
+ * suitable for use as a local.json file.
+ */
+
+require_once '/app/phabricator/scripts/init/init-setup.php';
+
+$console = PhutilConsole::getConsole();
+
+$options = PhabricatorApplicationConfigOptions::loadAllOptions();
+
+$result = array();
+
+foreach ($options as $option) {
+  $key = $option->getKey();
+  $final_value = null;
+
+  $config = new PhabricatorConfigLocalSource();
+  $local_value = $config->getKeys(array($key));
+  if (!empty($local_value)) {
+    $final_value = reset($local_value);
+  }
+
+  try {
+    $database_config = new PhabricatorConfigDatabaseSource('default');
+    $database_value = $database_config->getKeys(array($key));
+    if (!empty($database_value)) {
+      $final_value = reset($database_value);
+    }
+  } catch (Exception $e) {}
+
+  // null values will fall back to the coded default
+  if ($final_value) {
+    $result[$key] = $final_value;
+  }
+}
+
+$json = new PhutilJSON();
+$console->writeOut($json->encodeFormatted($result));
\ No newline at end of file