diff --git a/buildVersionFile.php b/buildVersionFile.php
index ee4a8b07..c90a68c9 100644
--- a/buildVersionFile.php
+++ b/buildVersionFile.php
@@ -1,7 +1,8 @@
 <?php
 
+declare(strict_types=1);
 
-$currentTag = trim(shell_exec('git describe --tags'));
+$currentTag = trim(shell_exec('git describe --tags') ?? '');
 exec('git diff-files --quiet', $output, $returnValue);
 
 $dirty = $returnValue === 0 ? '' : ' dirty';
diff --git a/index.php b/index.php
index 1fe13825..1b804488 100644
--- a/index.php
+++ b/index.php
@@ -1,4 +1,7 @@
 <?php
+
+declare(strict_types=1);
+
 /**
  * @copyright Copyright (c) 2016-2017 Lukas Reschke <lukas@statuscode.ch>
  * @copyright Copyright (c) 2016 Morris Jobke <hey@morrisjobke.de>
diff --git a/index.web.php b/index.web.php
index 32fde905..2274264f 100644
--- a/index.web.php
+++ b/index.web.php
@@ -1,4 +1,7 @@
 <?php
+
+declare(strict_types=1);
+
 /**
  * @copyright Copyright (c) 2016-2017 Lukas Reschke <lukas@statuscode.ch>
  * @copyright Copyright (c) 2016 Morris Jobke <hey@morrisjobke.de>
diff --git a/lib/CommandApplication.php b/lib/CommandApplication.php
index 563cfa06..fa6d50a0 100644
--- a/lib/CommandApplication.php
+++ b/lib/CommandApplication.php
@@ -1,4 +1,7 @@
 <?php
+
+declare(strict_types=1);
+
 /**
  * @copyright Copyright (c) 2016 Morris Jobke <hey@morrisjobke.de>
  *
diff --git a/lib/LogException.php b/lib/LogException.php
index 182f5797..6e4d033f 100644
--- a/lib/LogException.php
+++ b/lib/LogException.php
@@ -1,4 +1,7 @@
 <?php
+
+declare(strict_types=1);
+
 /**
  * @copyright Copyright (c) 2016 Lukas Reschke <lukas@statuscode.ch>
  * @copyright Copyright (c) 2016 Morris Jobke <hey@morrisjobke.de>
diff --git a/lib/RecursiveDirectoryIteratorWithoutData.php b/lib/RecursiveDirectoryIteratorWithoutData.php
index 52980eb7..8aec1f50 100644
--- a/lib/RecursiveDirectoryIteratorWithoutData.php
+++ b/lib/RecursiveDirectoryIteratorWithoutData.php
@@ -1,4 +1,7 @@
 <?php
+
+declare(strict_types=1);
+
 /**
  * @copyright Copyright (c) 2016 Lukas Reschke <lukas@statuscode.ch>
  * @copyright Copyright (c) 2016 Morris Jobke <hey@morrisjobke.de>
diff --git a/lib/UpdateCommand.php b/lib/UpdateCommand.php
index 5db19cc4..2c7c75bb 100644
--- a/lib/UpdateCommand.php
+++ b/lib/UpdateCommand.php
@@ -1,4 +1,7 @@
 <?php
+
+declare(strict_types=1);
+
 /**
  * @copyright Copyright (c) 2016 Morris Jobke <hey@morrisjobke.de>
  * @copyright Copyright (c) 2017 Lukas Reschke <lukas@statuscode.ch>
diff --git a/lib/UpdateException.php b/lib/UpdateException.php
index 0b263f8c..9091e62e 100644
--- a/lib/UpdateException.php
+++ b/lib/UpdateException.php
@@ -1,4 +1,7 @@
 <?php
+
+declare(strict_types=1);
+
 /**
  * @copyright Copyright (c) 2016 Lukas Reschke <lukas@statuscode.ch>
  * @copyright Copyright (c) 2016 Morris Jobke <hey@morrisjobke.de>
diff --git a/lib/Updater.php b/lib/Updater.php
index a7e61722..df188d7c 100644
--- a/lib/Updater.php
+++ b/lib/Updater.php
@@ -1,4 +1,7 @@
 <?php
+
+declare(strict_types=1);
+
 /**
  * @copyright Copyright (c) 2016-2017 Lukas Reschke <lukas@statuscode.ch>
  * @copyright Copyright (c) 2016 Morris Jobke <hey@morrisjobke.de>
diff --git a/updater.phar b/updater.phar
index 4a38828c..ee0db8d1 100755
Binary files a/updater.phar and b/updater.phar differ
diff --git a/updater.php b/updater.php
index 1c647968..98e44ae6 100755
--- a/updater.php
+++ b/updater.php
@@ -1,6 +1,8 @@
 #!/usr/bin/env php
 <?php
 
+declare(strict_types=1);
+
 require __DIR__ . '/vendor/autoload.php';
 
 ini_set('display_errors', '0');