diff --git a/docs/en/04_Changelogs/4.0.0.md b/docs/en/04_Changelogs/4.0.0.md
index 506df190d..57c801390 100644
--- a/docs/en/04_Changelogs/4.0.0.md
+++ b/docs/en/04_Changelogs/4.0.0.md
@@ -1295,6 +1295,7 @@ After (`mysite/_config/config.yml`):
 * `Injector` now complies with [PSR-11](https://github.com/php-fig/fig-standards/blob/master/accepted/PSR-11-container.md).
   Accordingly, `hasService()` has been renamed to `has()`, and `get()` will throw
   `SilverStripe\Core\Injector\InjectorNotFoundException` when the service can't be found.
+* Removed `CustomMethods::createMethod()`. Use closures instead.
 
 #### <a name="overview-general-deprecated"></a>General and Core Deprecated API
 
diff --git a/src/Core/CustomMethods.php b/src/Core/CustomMethods.php
index 1810e0e1b..12b7996d4 100644
--- a/src/Core/CustomMethods.php
+++ b/src/Core/CustomMethods.php
@@ -292,20 +292,4 @@ trait CustomMethods
             'method' => $method
         );
     }
-
-    /**
-     * Add an extra method using raw PHP code passed as a string
-     *
-     * @param string $method the method name
-     * @param string $code the PHP code - arguments will be in an array called $args, while you can access this object
-     *        by using $obj. Note that you cannot call protected methods, as the method is actually an external
-     *        function
-     */
-    protected function createMethod($method, $code)
-    {
-        $class = get_class($this);
-        self::$extra_methods[$class][strtolower($method)] = array (
-            'function' => create_function('$obj, $args', $code)
-        );
-    }
 }
diff --git a/src/Dev/Install/install.php5 b/src/Dev/Install/install.php5
index 44fa5e712..f13633153 100755
--- a/src/Dev/Install/install.php5
+++ b/src/Dev/Install/install.php5
@@ -1389,7 +1389,9 @@ class Installer extends InstallRequirements {
 		$locale = isset($_POST['locale']) ? addcslashes($_POST['locale'], "\'") : 'en_US';
 		$type = addcslashes($config['db']['type'], "\'");
 		$dbConfig = $config['db'][$type];
-		$dbConfig = array_map(create_function('$v', 'return addcslashes($v, "\\\'");'), $dbConfig);
+        foreach ($dbConfig as &$configValue) {
+            $configValue = addcslashes($configValue, "\\\'");
+        }
 		if(!isset($dbConfig['path'])) $dbConfig['path'] = '';
 		if(!$dbConfig) {
 			echo "<p style=\"color: red\">Bad config submitted</p><pre>";
diff --git a/src/Forms/Form.php b/src/Forms/Form.php
index 63dac2354..5e0ec417c 100644
--- a/src/Forms/Form.php
+++ b/src/Forms/Form.php
@@ -826,7 +826,9 @@ class Form extends ViewableData implements HasRequestHandler
         $attrs = $this->getAttributes();
 
         // Remove empty
-        $attrs = array_filter((array)$attrs, create_function('$v', 'return ($v || $v === 0);'));
+        $attrs = array_filter((array)$attrs, function ($value) {
+            return ($value || $value === 0);
+        });
 
         // Remove excluded
         if ($exclude) {
diff --git a/tests/php/Core/ObjectTest/T2.php b/tests/php/Core/ObjectTest/T2.php
index c6db8b7bd..7fc888fac 100644
--- a/tests/php/Core/ObjectTest/T2.php
+++ b/tests/php/Core/ObjectTest/T2.php
@@ -25,8 +25,6 @@ class T2 extends Object
         $this->addMethodsFrom('failover');
         $this->addMethodsFrom('failoverArr', 0);
         $this->addMethodsFrom('failoverArr', 1);
-
-        $this->createMethod('testCreateMethod', 'return "created";');
     }
 
     public function wrappedMethod($val)