diff --git a/lib/ArangoDBClient/Autoloader.php b/lib/ArangoDBClient/Autoloader.php
index <HASH>..<HASH> 100644
--- a/lib/ArangoDBClient/Autoloader.php
+++ b/lib/ArangoDBClient/Autoloader.php
@@ -87,7 +87,7 @@ class Autoloader
      */
     private static function checkEnvironment()
     {
-        list($major, $minor) = explode('.', phpversion());
+        list($major, $minor) = explode('.', PHP_VERSION);
 
         if ((int) $major < 5 || ((int) $major === 5 && (int) $minor < 6)) {
             throw new ClientException('Incompatible PHP environment. Expecting PHP 5.6 or higher');
diff --git a/lib/ArangoDBClient/HttpHelper.php b/lib/ArangoDBClient/HttpHelper.php
index <HASH>..<HASH> 100644
--- a/lib/ArangoDBClient/HttpHelper.php
+++ b/lib/ArangoDBClient/HttpHelper.php
@@ -257,7 +257,7 @@ class HttpHelper
                     $contentLength    = (int) substr($result, $pos + 16, 10); // 16 = strlen("content-length: ")
                     $contentLengthPos = $pos + 17; // 17 = 16 + 1 one digit
 
-                    if ($method === "HEAD") {
+                    if ($method === 'HEAD') {
                         // for HTTP HEAD requests, the server will respond
                         // with the proper Content-Length value, but will
                         // NOT return the body.
Codestyle + better retrieval of PHPVersion (through constant instead of function call)