diff --git a/composer.json b/composer.json
index 6254d0e..e14d089 100644
--- a/composer.json
+++ b/composer.json
@@ -17,12 +17,20 @@
         "issues": "https://github.com/RobThree/TwoFactorAuth/issues",
         "source": "https://github.com/RobThree/TwoFactorAuth"
     },
-    "autoload": {
-        "classmap": [
-            "lib/"
-        ]
-    },
     "require": {
         "php": ">=5.3.0"
+    },
+    "require-dev": {
+        "phpunit/phpunit": "@stable"
+    },
+    "autoload": {
+        "psr-4": {
+            "RobThree\\Auth\\": "lib"
+        }
+    },
+    "autoload-dev": {
+        "psr-4": {
+            "RobThree\\Auth\\Test\\": "tests"
+        }
     }
 }