diff --git a/res/composer-schema.json b/res/composer-schema.json
index e3599485f..180656c1d 100644
--- a/res/composer-schema.json
+++ b/res/composer-schema.json
@@ -177,7 +177,7 @@
                     "description": "The default style of handling dirty updates, defaults to false and can be any of true, false or \"stash\"."
                 },
                 "autoloader-suffix": {
-                    "type": ["string", "boolean"],
+                    "type": "string",
                     "description": "Optional string to be used as a suffix to the autoloader generator. When null a random one will be generated."
                 },
                 "prepend-autoloader": {
diff --git a/src/Composer/Autoload/AutoloadGenerator.php b/src/Composer/Autoload/AutoloadGenerator.php
index 7b019e012..b26fb5831 100644
--- a/src/Composer/Autoload/AutoloadGenerator.php
+++ b/src/Composer/Autoload/AutoloadGenerator.php
@@ -169,7 +169,7 @@ EOF;
         $classmapFile .= ");\n";
 
         if (!$suffix) {
-            $suffix = $config->get('autoloader-suffix') ? $config->get('autoloader-suffix') : md5(uniqid('', true));
+            $suffix = $config->get('autoloader-suffix') ?: md5(uniqid('', true));
         }
 
         file_put_contents($targetDir.'/autoload_namespaces.php', $namespacesFile);
diff --git a/src/Composer/Config.php b/src/Composer/Config.php
index 68a3410f3..311c7de85 100644
--- a/src/Composer/Config.php
+++ b/src/Composer/Config.php
@@ -35,7 +35,7 @@ class Config
         'cache-files-ttl' => null, // fallback to cache-ttl
         'cache-files-maxsize' => '300MiB',
         'discard-changes' => false,
-        'autoload-suffix' => false,
+        'autoload-suffix' => null,
         'prepend-autoloader' => true,
         'github-domains' => array('github.com'),
     );