diff --git a/aufgaben/elm.json b/aufgaben/elm.json
index f2de947..3246338 100644
--- a/aufgaben/elm.json
+++ b/aufgaben/elm.json
@@ -1,25 +1,29 @@
 {
-  "type": "application",
-  "source-directories": [
-    "src"
-  ],
-  "elm-version": "0.19.1",
-  "dependencies": {
-    "direct": {
-      "elm/browser": "1.0.2",
-      "elm/core": "1.0.5",
-      "elm/html": "1.0.0",
-      "elm/random": "1.0.0"
+    "type": "application",
+    "source-directories": [
+        "src"
+    ],
+    "elm-version": "0.19.1",
+    "dependencies": {
+        "direct": {
+            "elm/browser": "1.0.2",
+            "elm/core": "1.0.5",
+            "elm/html": "1.0.0",
+            "elm/random": "1.0.0"
+        },
+        "indirect": {
+            "elm/json": "1.1.3",
+            "elm/time": "1.0.0",
+            "elm/url": "1.0.0",
+            "elm/virtual-dom": "1.0.3"
+        }
     },
-    "indirect": {
-      "elm/json": "1.1.3",
-      "elm/time": "1.0.0",
-      "elm/url": "1.0.0",
-      "elm/virtual-dom": "1.0.3"
+    "test-dependencies": {
+        "direct": {
+            "elm-explorations/test": "2.0.1"
+        },
+        "indirect": {
+            "elm/bytes": "1.0.8"
+        }
     }
-  },
-  "test-dependencies": {
-    "direct": {},
-    "indirect": {}
-  }
 }
diff --git a/aufgaben/src/Pflichtuebung_01/Pu01.elm b/aufgaben/src/Pflichtuebung_01/Pu01.elm
index 9b65c06..7dfeb91 100644
--- a/aufgaben/src/Pflichtuebung_01/Pu01.elm
+++ b/aufgaben/src/Pflichtuebung_01/Pu01.elm
@@ -1,3 +1,5 @@
+module Pflichtuebung_01.Pu01 exposing (..)
+
 type alias Day =
     Int
 
diff --git a/aufgaben/tests/Pflichtuebung_01/Pu01Tests.elm b/aufgaben/tests/Pflichtuebung_01/Pu01Tests.elm
new file mode 100644
index 0000000..efcdbae
--- /dev/null
+++ b/aufgaben/tests/Pflichtuebung_01/Pu01Tests.elm
@@ -0,0 +1,10 @@
+module Pflichtuebung_01.Pu01Tests exposing (..)
+
+import Expect exposing (Expectation)
+import Fuzz exposing (Fuzzer, int, list, string)
+import Test exposing (..)
+
+
+suite : Test
+suite =
+    todo "Implement our first test. See https://package.elm-lang.org/packages/elm-explorations/test/latest for how to do this!"