diff --git a/actions/ConnectivityAction.php b/actions/ConnectivityAction.php
index ea8cb54f..a24b4901 100644
--- a/actions/ConnectivityAction.php
+++ b/actions/ConnectivityAction.php
@@ -55,7 +55,6 @@ class ConnectivityAction extends ActionAbstract {
 	private function reportBridgeConnectivity($bridgeName) {
 
 		$bridgeFac = new \BridgeFactory();
-		$bridgeFac->setWorkingDir(PATH_LIB_BRIDGES);
 
 		if(!$bridgeFac->isWhitelisted($bridgeName)) {
 			header('Content-Type: text/html');
diff --git a/actions/DetectAction.php b/actions/DetectAction.php
index 86605de4..e58aee93 100644
--- a/actions/DetectAction.php
+++ b/actions/DetectAction.php
@@ -20,7 +20,6 @@ class DetectAction extends ActionAbstract {
 			or returnClientError('You must specify a format!');
 
 		$bridgeFac = new \BridgeFactory();
-		$bridgeFac->setWorkingDir(PATH_LIB_BRIDGES);
 
 		foreach($bridgeFac->getBridgeNames() as $bridgeName) {
 
diff --git a/actions/DisplayAction.php b/actions/DisplayAction.php
index 6f3b997a..99dd21ce 100644
--- a/actions/DisplayAction.php
+++ b/actions/DisplayAction.php
@@ -28,7 +28,6 @@ class DisplayAction extends ActionAbstract {
 			or returnClientError('You must specify a format!');
 
 		$bridgeFac = new \BridgeFactory();
-		$bridgeFac->setWorkingDir(PATH_LIB_BRIDGES);
 
 		// whitelist control
 		if(!$bridgeFac->isWhitelisted($bridge)) {
diff --git a/actions/ListAction.php b/actions/ListAction.php
index f3509564..f7b92063 100644
--- a/actions/ListAction.php
+++ b/actions/ListAction.php
@@ -18,7 +18,6 @@ class ListAction extends ActionAbstract {
 		$list->total = 0;
 
 		$bridgeFac = new \BridgeFactory();
-		$bridgeFac->setWorkingDir(PATH_LIB_BRIDGES);
 
 		foreach($bridgeFac->getBridgeNames() as $bridgeName) {
 
diff --git a/lib/BridgeCard.php b/lib/BridgeCard.php
index ebd958fb..befde86a 100644
--- a/lib/BridgeCard.php
+++ b/lib/BridgeCard.php
@@ -289,7 +289,6 @@ This bridge is not fetching its content through a secure connection</div>';
 	static function displayBridgeCard($bridgeName, $formats, $isActive = true){
 
 		$bridgeFac = new \BridgeFactory();
-		$bridgeFac->setWorkingDir(PATH_LIB_BRIDGES);
 
 		$bridge = $bridgeFac->create($bridgeName);
 
diff --git a/lib/BridgeFactory.php b/lib/BridgeFactory.php
index 5281fa62..f435261c 100644
--- a/lib/BridgeFactory.php
+++ b/lib/BridgeFactory.php
@@ -1,240 +1,87 @@
 <?php
-/**
- * This file is part of RSS-Bridge, a PHP project capable of generating RSS and
- * Atom feeds for websites that don't have one.
- *
- * For the full license information, please view the UNLICENSE file distributed
- * with this source code.
- *
- * @package	Core
- * @license	http://unlicense.org/ UNLICENSE
- * @link	https://github.com/rss-bridge/rss-bridge
- */
 
-/**
- * Factory class responsible for creating bridge objects from a given working
- * directory, limited by a whitelist.
- *
- * This class is capable of:
- * - Locating bridge classes in the specified working directory (see {@see Bridge::$workingDir})
- * - Filtering bridges based on a whitelist (see {@see Bridge::$whitelist})
- * - Creating new bridge instances based on the bridge's name (see {@see Bridge::create()})
- *
- * The following example illustrates the intended use for this class.
- *
- * ```PHP
- * require_once __DIR__ . '/rssbridge.php';
- *
- * // Step 1: Set the working directory
- * Bridge::setWorkingDir(__DIR__ . '/../bridges/');
- *
- * // Step 2: Add bridges to the whitelist
- * Bridge::setWhitelist(array('GitHubIssue', 'GoogleSearch', 'Facebook', 'Twitter'));
- *
- * // Step 3: Create a new instance of a bridge (based on the name)
- * $bridge = Bridge::create('GitHubIssue');
- * ```
- */
-class BridgeFactory extends FactoryAbstract {
+final class BridgeFactory {
 
-	/**
-	 * Holds a list of whitelisted bridges.
-	 *
-	 * Do not access this property directly!
-	 * Use {@see Bridge::getWhitelist()} instead.
-	 *
-	 * @var array
-	 */
-	protected $whitelist = array();
+	private $folder;
+	private $bridgeNames = [];
+	private $whitelist = [];
 
-	/**
-	 * Creates a new bridge object from the working directory.
-	 *
-	 * @throws \InvalidArgumentException if the requested bridge name is invalid.
-	 * @throws \Exception if the requested bridge doesn't exist in the working
-	 * directory.
-	 * @param string $name Name of the bridge object.
-	 * @return object|bool The bridge object or false if the class is not instantiable.
-	 */
-	public function create($name){
-		if(!$this->isBridgeName($name)) {
-			throw new \InvalidArgumentException('Bridge name invalid!');
-		}
+	public function __construct(string $folder = PATH_LIB_BRIDGES)
+	{
+		$this->folder = $folder;
 
-		$name = $this->sanitizeBridgeName($name) . 'Bridge';
-		$filePath = $this->getWorkingDir() . $name . '.php';
-
-		if(!file_exists($filePath)) {
-			throw new \Exception('Bridge file ' . $filePath . ' does not exist!');
-		}
-
-		if((new \ReflectionClass($name))->isInstantiable()) {
-			return new $name();
-		}
-
-		return false;
-	}
-
-	/**
-	 * Returns true if the provided name is a valid bridge name.
-	 *
-	 * A valid bridge name starts with a capital letter ([A-Z]), followed by
-	 * zero or more alphanumeric characters or hyphen ([A-Za-z0-9-]).
-	 *
-	 * @param string $name The bridge name.
-	 * @return bool true if the name is a valid bridge name, false otherwise.
-	 */
-	public function isBridgeName($name){
-		return is_string($name) && preg_match('/^[A-Z][a-zA-Z0-9-]*$/', $name) === 1;
-	}
-
-	/**
-	 * Returns the list of bridge names from the working directory.
-	 *
-	 * The list is cached internally to allow for successive calls.
-	 *
-	 * @return array List of bridge names
-	 */
-	public function getBridgeNames(){
-
-		static $bridgeNames = array(); // Initialized on first call
-
-		if(empty($bridgeNames)) {
-			$files = scandir($this->getWorkingDir());
-
-			if($files !== false) {
-				foreach($files as $file) {
-					if(preg_match('/^([^.]+)Bridge\.php$/U', $file, $out)) {
-						$bridgeNames[] = $out[1];
-					}
-				}
+		// create names
+		foreach(scandir($this->folder) as $file) {
+			if(preg_match('/^([^.]+)Bridge\.php$/U', $file, $m)) {
+				$this->bridgeNames[] = $m[1];
 			}
 		}
 
-		return $bridgeNames;
+		// create whitelist
+		if (file_exists(WHITELIST)) {
+			$contents = trim(file_get_contents(WHITELIST));
+		} elseif (file_exists(WHITELIST_DEFAULT)) {
+			$contents = trim(file_get_contents(WHITELIST_DEFAULT));
+		} else {
+			$contents = '';
+		}
+		if ($contents === '*') { // Whitelist all bridges
+			$this->whitelist = $this->getBridgeNames();
+		} else {
+			foreach (explode("\n", $contents) as $bridgeName) {
+				$this->whitelist[] = $this->sanitizeBridgeName($bridgeName);
+			}
+		}
 	}
 
-	/**
-	 * Checks if a bridge is whitelisted.
-	 *
-	 * @param string $name Name of the bridge.
-	 * @return bool True if the bridge is whitelisted.
-	 */
-	public function isWhitelisted($name){
-		return in_array($this->sanitizeBridgeName($name), $this->getWhitelist());
+	public function create(string $name): BridgeInterface
+	{
+		if(preg_match('/^[A-Z][a-zA-Z0-9-]*$/', $name)) {
+			$className = sprintf('%sBridge', $this->sanitizeBridgeName($name));
+			return new $className();
+		}
+		throw new \InvalidArgumentException('Bridge name invalid!');
 	}
 
-	/**
-	 * Returns the whitelist.
-	 *
-	 * On first call this function reads the whitelist from {@see WHITELIST} if
-	 * the file exists, {@see WHITELIST_DEFAULT} otherwise.
-	 * * Each line in the file specifies one bridge on the whitelist.
-	 * * An empty file disables all bridges.
-	 * * If the file only only contains `*`, all bridges are whitelisted.
-	 *
-	 * Use {@see Bridge::setWhitelist()} to specify a default whitelist **before**
-	 * calling this function! The list is cached internally to allow for
-	 * successive calls. If {@see Bridge::setWhitelist()} gets called after this
-	 * function, the whitelist is **not** updated again!
-	 *
-	 * @return array Array of whitelisted bridges
-	 */
-	public function getWhitelist() {
+	public function getBridgeNames(): array
+	{
+		return $this->bridgeNames;
+	}
 
-		static $firstCall = true; // Initialized on first call
+	public function isWhitelisted($name): bool
+	{
+		return in_array($this->sanitizeBridgeName($name), $this->whitelist);
+	}
 
-		if($firstCall) {
-
-			if(file_exists(WHITELIST)) {
-				$contents = trim(file_get_contents(WHITELIST));
-			} elseif(file_exists(WHITELIST_DEFAULT)) {
-				$contents = trim(file_get_contents(WHITELIST_DEFAULT));
-			} else {
-				$contents = '';
-			}
-
-			if($contents === '*') { // Whitelist all bridges
-				$this->whitelist = $this->getBridgeNames();
-			} else {
-				//$this->$whitelist = array_map('$this->sanitizeBridgeName', explode("\n", $contents));
-				foreach(explode("\n", $contents) as $bridgeName) {
-					$this->whitelist[] = $this->sanitizeBridgeName($bridgeName);
-				}
-			}
+	private function sanitizeBridgeName($name) {
 
+		if(!is_string($name)) {
+			return null;
 		}
 
-		return $this->whitelist;
-
-	}
-
-	/**
-	 * Sets the (default) whitelist.
-	 *
-	 * If this function is called **before** {@see Bridge::getWhitelist()}, the
-	 * provided whitelist will be replaced by a custom whitelist specified in
-	 * {@see WHITELIST} (if it exists).
-	 *
-	 * If this function is called **after** {@see Bridge::getWhitelist()}, the
-	 * provided whitelist is taken as is (not updated by the custom whitelist
-	 * again).
-	 *
-	 * @param array $default The whitelist as array of bridge names.
-	 * @return void
-	 */
-	public function setWhitelist($default = array()) {
-		$this->whitelist = array_map('$this->sanitizeBridgeName', $default);
-	}
-
-	/**
-	 * Returns the sanitized bridge name.
-	 *
-	 * The bridge name can be specified in various ways:
-	 * * The PHP file name (i.e. `GitHubIssueBridge.php`)
-	 * * The PHP file name without file extension (i.e. `GitHubIssueBridge`)
-	 * * The bridge name (i.e. `GitHubIssue`)
-	 *
-	 * Casing is ignored (i.e. `GITHUBISSUE` and `githubissue` are the same).
-	 *
-	 * A bridge file matching the given bridge name must exist in the working
-	 * directory!
-	 *
-	 * @param string $name The bridge name
-	 * @return string|null The sanitized bridge name if the provided name is
-	 * valid, null otherwise.
-	 */
-	protected function sanitizeBridgeName($name) {
-
-		if(is_string($name)) {
-
-			// Trim trailing '.php' if exists
-			if(preg_match('/(.+)(?:\.php)/', $name, $matches)) {
-				$name = $matches[1];
-			}
-
-			// Trim trailing 'Bridge' if exists
-			if(preg_match('/(.+)(?:Bridge)/i', $name, $matches)) {
-				$name = $matches[1];
-			}
-
-			// Improve performance for correctly written bridge names
-			if(in_array($name, $this->getBridgeNames())) {
-				$index = array_search($name, $this->getBridgeNames());
-				return $this->getBridgeNames()[$index];
-			}
-
-			// The name is valid if a corresponding bridge file is found on disk
-			if(in_array(strtolower($name), array_map('strtolower', $this->getBridgeNames()))) {
-				$index = array_search(strtolower($name), array_map('strtolower', $this->getBridgeNames()));
-				return $this->getBridgeNames()[$index];
-			}
-
-			Debug::log('Invalid bridge name specified: "' . $name . '"!');
-
+		// Trim trailing '.php' if exists
+		if (preg_match('/(.+)(?:\.php)/', $name, $matches)) {
+			$name = $matches[1];
 		}
 
-		return null; // Bad parameter
+		// Trim trailing 'Bridge' if exists
+		if (preg_match('/(.+)(?:Bridge)/i', $name, $matches)) {
+			$name = $matches[1];
+		}
 
+		// Improve performance for correctly written bridge names
+		if (in_array($name, $this->getBridgeNames())) {
+			$index = array_search($name, $this->getBridgeNames());
+			return $this->getBridgeNames()[$index];
+		}
+
+		// The name is valid if a corresponding bridge file is found on disk
+		if (in_array(strtolower($name), array_map('strtolower', $this->getBridgeNames()))) {
+			$index = array_search(strtolower($name), array_map('strtolower', $this->getBridgeNames()));
+			return $this->getBridgeNames()[$index];
+		}
+
+		Debug::log('Invalid bridge name specified: "' . $name . '"!');
+		return null;
 	}
 }
diff --git a/lib/BridgeList.php b/lib/BridgeList.php
index 7b2d5268..4aca037c 100644
--- a/lib/BridgeList.php
+++ b/lib/BridgeList.php
@@ -63,7 +63,6 @@ EOD;
 		$inactiveBridges = '';
 
 		$bridgeFac = new \BridgeFactory();
-		$bridgeFac->setWorkingDir(PATH_LIB_BRIDGES);
 		$bridgeList = $bridgeFac->getBridgeNames();
 
 		$formatFac = new FormatFactory();
diff --git a/tests/ListActionTest.php b/tests/ListActionTest.php
index f15e1b73..e914b7d3 100644
--- a/tests/ListActionTest.php
+++ b/tests/ListActionTest.php
@@ -41,7 +41,6 @@ class ListActionTest extends TestCase {
 		);
 
 		$bridgeFac = new BridgeFactory();
-		$bridgeFac->setWorkingDir(PATH_LIB_BRIDGES);
 
 		$this->assertEquals(
 			count($bridgeFac->getBridgeNames()),