diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 08a594b..4da561e 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -8,8 +8,8 @@ on:
 
 jobs:
   tests:
-    name: Python ${{ matrix.python_version }}
-    runs-on: ubuntu-latest
+    name: Python ${{ matrix.python_version }} on ${{ matrix.os }}
+    runs-on: ${{ matrix.os }}
     strategy:
       fail-fast: false
       matrix:
@@ -18,6 +18,10 @@ jobs:
           - "3.8"
           - "3.9"
           - "3.10"
+        os:
+          - ubuntu-latest
+          - windows-latest
+          - macos-latest
     steps:
       - uses: actions/checkout@v3
 
@@ -29,9 +33,9 @@ jobs:
 
       - name: Install dependencies
         run: |
-          pip install -U pip poetry
-          poetry install
+          python3 -m pip install -U pip poetry
+          python3 -m poetry install
 
       - name: Run Tests
         run: |
-          poetry run pytest tests.py
+          python3 -m poetry run pytest tests.py
diff --git a/checksitemap/__main__.py b/checksitemap/__main__.py
index 942a733..aa3af04 100644
--- a/checksitemap/__main__.py
+++ b/checksitemap/__main__.py
@@ -19,3 +19,7 @@ def main():
         sys.exit(1)
     except KeyboardInterrupt:
         sys.exit(-1)
+
+
+if __name__ == '__main__':
+    main()
diff --git a/tests.py b/tests.py
index 7a61cbb..ad6d52a 100644
--- a/tests.py
+++ b/tests.py
@@ -3,8 +3,8 @@
 from aurornis import run
 
 
-def run_cmd(xml: str):
-    return run(["checksitemap", xml])
+def run_cmd(path: str):
+    return run(["python3", "-m", "checksitemap", path], normalize_carriage_return=True)
 
 
 def test_check_valid_sitemap_from_local_file():
@@ -15,7 +15,7 @@ def test_check_valid_sitemap_from_local_file():
 
 
 def test_check_invalid_sitemap_from_local_file_missing_namespace():
-    result = run_cmd(f"test_assets/invalid_sitemap_missing_namespace.xml")
+    result = run_cmd("test_assets/invalid_sitemap_missing_namespace.xml")
     assert not result.is_successful()
     assert (
         result.stderr == "Warning: missing XML namespace on <urlset> tag: "
@@ -25,21 +25,21 @@ def test_check_invalid_sitemap_from_local_file_missing_namespace():
 
 
 def test_check_invalid_sitemap_from_local_file_invalid_tag():
-    result = run_cmd(f"test_assets/invalid_sitemap_invalid_tag.xml")
+    result = run_cmd("test_assets/invalid_sitemap_invalid_tag.xml")
     assert not result.is_successful()
     assert result.stderr == "Error: invalid <is_a_cool_page> tag for URL n°1!\n"
     assert result.stdout == "\n2 of 3 URLs (66%) passed.\n"
 
 
 def test_check_invalid_sitemap_from_local_file_missing_loc():
-    result = run_cmd(f"test_assets/invalid_sitemap_missing_loc.xml")
+    result = run_cmd("test_assets/invalid_sitemap_missing_loc.xml")
     assert not result.is_successful()
     assert result.stderr == "Error: URL n°1 has no mandatory <loc> tag!\n"
     assert result.stdout == "\n2 of 3 URLs (66%) passed.\n"
 
 
 def test_check_invalid_sitemap_from_local_file_invalid_priority():
-    result = run_cmd(f"test_assets/invalid_sitemap_invalid_priority.xml")
+    result = run_cmd("test_assets/invalid_sitemap_invalid_priority.xml")
     assert not result.is_successful()
     assert (
         result.stderr
@@ -49,7 +49,7 @@ def test_check_invalid_sitemap_from_local_file_invalid_priority():
 
 
 def test_check_invalid_sitemap_from_local_file_changefreq():
-    result = run_cmd(f"test_assets/invalid_sitemap_changefreq.xml")
+    result = run_cmd("test_assets/invalid_sitemap_changefreq.xml")
     assert not result.is_successful()
     assert (
         result.stderr