diff --git a/.github/workflows/unittests.yml b/.github/workflows/unittests.yml
index 70eda8a..0757cfb 100644
--- a/.github/workflows/unittests.yml
+++ b/.github/workflows/unittests.yml
@@ -1,6 +1,10 @@
 name: Python package
 
-on: [push]
+on:
+  push:
+    branches: [master]
+  pull_request:
+    branches: [master]
 
 jobs:
   build:
@@ -19,6 +23,6 @@ jobs:
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip
-          if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
+          pip install -r requirements.txt
       - name: Run unittests
         run: python -m unittest discover
\ No newline at end of file