diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..0db5e9b
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,11 @@
+name: CI
+on:
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Say hello
+        run: echo "Hello world!"
diff --git a/app.py b/app.py
index 1059467..b1d86a9 100644
--- a/app.py
+++ b/app.py
@@ -2,3 +2,5 @@ def calculator(a: int, b: int) -> int:
     return a + b
 
 
+def devide(a: int, b: int) -> int:
+    return a / b
\ No newline at end of file