turns out I had a global gitignore with lib... -_-'

.github/workflows/test.yml

@@ -25,5 +25,5 @@ jobs:
     - uses: ramsey/composer-install@v2
 
     - run: composer lint-ci
-    - run: composer test
     - run: composer phpstan
+    - run: composer test

lib/Algorithm.php

@@ -0,0 +1,14 @@
+<?php declare(strict_types=1);
+
+namespace RobThree\Auth;
+
+/**
+ * List of supported cryptographic algorithms
+ */
+enum Algorithm: string
+{
+    case Md5 = 'md5';
+    case Sha1 = 'sha1';
+    case Sha256 = 'sha256';
+    case Sha512 = 'sha512';
+}