diff --git a/composer.json b/composer.json
index d86702a..08b3a46 100644
--- a/composer.json
+++ b/composer.json
@@ -24,7 +24,7 @@
 		}
 	},
 	"require": {
-		"pattern-lab/core": "dev-dev",
+		"pattern-lab/core": "^2.0.0",
 		"twig/twig":        "~1.0"
 	},
 	"extra": {
diff --git a/src/PatternLab/PatternEngine/Twig/Loaders/PatternLoader.php b/src/PatternLab/PatternEngine/Twig/Loaders/PatternLoader.php
index 3d01683..fa2ce2f 100644
--- a/src/PatternLab/PatternEngine/Twig/Loaders/PatternLoader.php
+++ b/src/PatternLab/PatternEngine/Twig/Loaders/PatternLoader.php
@@ -64,13 +64,26 @@ public function __construct($options = array()) {
 		// set-up the loader list in order that they should be checked
 		// 1. Patterns 2. Filesystem 3. String
 		$loaders   = array();
+		// 1. add Patterns
 		$loaders[] = new Twig_Loader_PatternPartialLoader(Config::getOption("patternSourceDir"),array("patternPaths" => $options["patternPaths"]));
 
-		// add the paths to the filesystem loader if the paths existed
+		// 2. add the paths to the filesystem loader if the paths existed
 		if (count($filesystemLoaderPaths) > 0) {
 			$filesystemLoader = new \Twig_Loader_Filesystem($filesystemLoaderPaths);
 			$loaders[] = TwigUtil::addPaths($filesystemLoader, $patternSourceDir);
 		}
+
+		// Setting loaders and giving plugins a chance to manipulate them
+		TwigUtil::setLoaders($loaders);
+		// set-up the dispatcher
+		$dispatcherInstance = Dispatcher::getInstance();
+		$dispatcherInstance->dispatch("twigLoaderPreInit.customize");
+		// getting the loaders back
+		$loaders = TwigUtil::getLoaders();
+
+		// 3. add String loader
+		// This *must* go last or no loaders after will work ~ https://github.com/symfony/symfony/issues/10865
+		// @todo Remove `Twig_Loader_String` - if a Twig include path is wrong, this outputs the string anyway with no error ~ https://github.com/symfony/symfony/issues/10865
 		$loaders[] = new \Twig_Loader_String();
 		
 		// set-up Twig
@@ -87,8 +100,6 @@ public function __construct($options = array()) {
 		TwigUtil::loadDebug();
 		TwigUtil::loadMacros();
 
-		// set-up the dispatcher
-		$dispatcherInstance = Dispatcher::getInstance();
 		$dispatcherInstance->dispatch("twigLoader.customize");
 		$dispatcherInstance->dispatch("twigPatternLoader.customize");
 
@@ -105,7 +116,17 @@ public function __construct($options = array()) {
 	*/
 	public function render($options = array()) {
 		
-		return $this->instance->render($options["pattern"], $options["data"]);
+		$result = $this->instance->render($options["pattern"], $options["data"]);
+		// This error handler catches files that didn't render using any of the loaders.
+		// The most common scenario is when a file's contents get passed to and through `Twig_Loader_String` and
+		// outputs the raw Twig file contents like `@atoms/buttons/button.twig`.
+		// @todo Remove this once `Twig_Loader_String` is removed.
+		if (strpos($result, "@") === 0) {
+			echo "Twig file not found: " . $result . "\n";
+			exit(1);
+		} else {
+			return $result;
+		}
 		
 	}
 	
diff --git a/src/PatternLab/PatternEngine/Twig/TwigUtil.php b/src/PatternLab/PatternEngine/Twig/TwigUtil.php
index eaedd53..64f97da 100644
--- a/src/PatternLab/PatternEngine/Twig/TwigUtil.php
+++ b/src/PatternLab/PatternEngine/Twig/TwigUtil.php
@@ -19,7 +19,8 @@
 class TwigUtil {
 	
 	protected static $instance = '';
-	
+	protected static $loaders = array();
+
 	/**
 	* Get an instance of the Twig environment
 	*
@@ -46,7 +47,46 @@ public static function setInstance($instance = "") {
 		}
 		
 		self::$instance = $instance;
-		
+
+	}
+
+	/**
+	* Get an instance of the Twig loaders
+	*
+	* @return {Array}       List of Twig Loaders
+	*/
+	public static function getLoaders() {
+
+		if (empty(self::$loaders)) {
+			return false;
+		}
+
+		return self::$loaders;
+
+	}
+
+	/**
+	* Set an instance of the Twig loaders
+	* @param  {Array}       List of Twig Loaders
+	*/
+	public static function setLoaders($loaders = array()) {
+
+		if (empty($loaders)) {
+			Console::writeError("please set the loaders");
+		}
+
+		self::$loaders = $loaders;
+
+	}
+
+	/**
+	* Add a loader to the Twig Loaders array
+	* @param  {Loader}       A Twig Loader
+	*/
+	public static function addLoader($loader) {
+
+		self::$loaders[] = $loader;
+
 	}
 	
 	/**
@@ -61,7 +101,8 @@ public static function addPaths($filesystemLoader, $patternSourceDir) {
 		$finder = new Finder();
 		$finder->directories()->depth(0)->in($patternSourceDir);
 		foreach ($finder as $file) {
-			$patternBits = explode("-",$file->getRelativePathName(),2);
+			$pattern = $file->getRelativePathName();
+			$patternBits = explode("-",$pattern,2);
 			$patternTypePath = (((int)$patternBits[0] != 0) || ($patternBits[0] == '00')) ? $patternBits[1] : $pattern;
 			$filesystemLoader->addPath($file->getPathName(), $patternTypePath);
 		}