diff --git a/.github/workflows/python-tests.yml b/.github/workflows/python-tests.yml
index a8200bd..cd3d885 100644
--- a/.github/workflows/python-tests.yml
+++ b/.github/workflows/python-tests.yml
@@ -13,30 +13,25 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - name: Checkout code
-      uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+      - name: Checkout code
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
 
-    - name: Extract Python version
-      id: py
-      run: |
-        echo "version=$(grep -oP 'target-version\s*=\s*"py\K[0-9]+' pyproject.toml)" >> "$GITHUB_OUTPUT"
+      - name: Set up Python
+        uses: actions/setup-python@a26af69be951a213d495a4c3e4e4022e16d87065 # v5.6.0
+        with:
+          python-version: "3.13.2"
 
-    - name: Set up Python
-      uses: actions/setup-python@a26af69be951a213d495a4c3e4e4022e16d87065 # v5.6.0
-      with:
-        python-version: "${{ steps.py.outputs.version }}"
+      - name: Install dependencies
+        shell: bash
+        run: |
+          python -m pip install --upgrade pip
+          pip install -r requirements.txt
 
-    - name: Install dependencies
-      shell: bash
-      run: |
-        python -m pip install --upgrade pip
-        pip install -r requirements.txt
+      - name: Run Ruff linting
+        shell: bash
+        run: ruff check .
 
-    - name: Run Ruff linting
-      shell: bash
-      run: ruff check .
-
-    - name: Run tests with coverage
-      shell: bash
-      run: |
-        pytest --cov=aeonview --cov-report=term-missing
+      - name: Run tests with coverage
+        shell: bash
+        run: |
+          pytest --cov=aeonview --cov-report=term-missing
diff --git a/.python-version b/.python-version
index 3b564fa..3e388a4 100644
--- a/.python-version
+++ b/.python-version
@@ -1 +1 @@
-3.11.12
+3.13.2
diff --git a/AGENTS.md b/AGENTS.md
index ab7f7c1..4fd092f 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -2,7 +2,7 @@
 
 ## Development Workflow
 
-- Use **Python 3.11** as defined in `.python-version`.
+- Use **Python 3.13** as defined in `.python-version`.
 - Install dependencies from `requirements.txt` (virtualenv recommended).
 - Use **pre-commit** for linting and testing:
   - `pre-commit run --files <changed files>`
diff --git a/README.md b/README.md
index ada3ef8..7bab427 100644
--- a/README.md
+++ b/README.md
@@ -26,7 +26,7 @@ Low quality sample: [aeonview 2min preview/Tampere Jan. 2008][sample]
 
 ## Requirements
 
-- Python 3.11+
+- Python 3.13+
 - `ffmpeg` and `curl` (system tools)
 - lots of hard drive space
 - Optional: `pyenv` for managing Python versions
diff --git a/aeonview_test.py b/aeonview_test.py
index 8fe358d..300cd09 100644
--- a/aeonview_test.py
+++ b/aeonview_test.py
@@ -28,9 +28,9 @@ tmp_images = Path(tempfile.gettempdir(), "images")
 
 
 def test_build_path_resolves_correctly():
-    base = Path("/tmp")
+    base = Path(tempfile.gettempdir())
     result = AeonViewHelpers.build_path(base, "a", "b", "c")
-    assert result == Path("/tmp/a/b/c").resolve()
+    assert result == Path(base, "a", "b", "c").resolve()
 
 
 def test_check_date_valid():
@@ -62,7 +62,7 @@ def test_get_extension_invalid():
 
 def test_generate_ffmpeg_command():
     input_dir = tmp_images
-    output_file = Path("/tmp/output.mp4")
+    output_file = Path(tempfile.gettempdir(), "output.mp4")
     fps = 24
     cmd = AeonViewHelpers.generate_ffmpeg_command(input_dir, output_file, fps)
     assert "ffmpeg" in cmd[0]
@@ -73,10 +73,10 @@ def test_generate_ffmpeg_command():
 
 def test_generate_ffmpeg_command_output_format():
     input_dir = tmp_images
-    output_file = Path("/tmp/video.mp4")
+    output_file = Path(tempfile.gettempdir(), "video.mp4")
     cmd = AeonViewHelpers.generate_ffmpeg_command(input_dir, output_file, 30)
-    assert "/tmp/images/*.{jpg,jpeg,png,gif,webp}" in cmd
-    assert "/tmp/video.mp4" in cmd
+    assert str(tmp_images / "*.{jpg,jpeg,png,gif,webp}") in cmd
+    assert str(output_file) in cmd
     assert "-c:v" in cmd
     assert "libx264" in cmd
     assert "-pix_fmt" in cmd
@@ -86,7 +86,7 @@ def test_generate_ffmpeg_command_output_format():
 @mock.patch("subprocess.run")
 def test_simulate_ffmpeg_call(mock_run):
     input_dir = tmp_images
-    output_file = Path("/tmp/out.mp4")
+    output_file = Path(tempfile.gettempdir(), "out.mp4")
     cmd = AeonViewHelpers.generate_ffmpeg_command(input_dir, output_file, 10)
     subprocess.run(cmd, check=True)
     mock_run.assert_called_once_with(cmd, check=True)
@@ -168,7 +168,7 @@ def test_download_image_failure(mock_get):
 
     args = argparse.Namespace(simulate=False)
     avi = AeonViewImages(default_test_path, f"{default_image_domain}.jpg", args)
-    destination = Path("/tmp/image.jpg")
+    destination = Path(tempfile.gettempdir(), "image.jpg")
 
     with pytest.raises(SystemExit), mock.patch("aeonview.logging.error"):
         avi.download_image(destination)
@@ -220,7 +220,7 @@ def test_generate_monthly_video_not_implemented():
     )
     avv = AeonViewVideos(default_test_path, args)
     with pytest.raises(NotImplementedError):
-        avv.generate_monthly_video(Path("/tmp"))
+        avv.generate_monthly_video(Path(tempfile.gettempdir()))
 
 
 def test_generate_yearly_video_not_implemented():
@@ -233,7 +233,7 @@ def test_generate_yearly_video_not_implemented():
     )
     avv = AeonViewVideos(default_test_path, args)
     with pytest.raises(NotImplementedError):
-        avv.generate_yearly_video(Path("/tmp"))
+        avv.generate_yearly_video(Path(tempfile.gettempdir()))
 
 
 @mock.patch("sys.argv", ["aeonview.py", "--mode", "image", "--url",
diff --git a/pyproject.toml b/pyproject.toml
index cb7d2ba..85de343 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,9 @@
 [tool.ruff]
 line-length = 80
-target-version = "py311"
+target-version = "py313"
+
+[project]
+requires-python = ">=3.13.2"
 
 [tool.ruff.lint]
 select = ["E", "F", "I", "B", "UP", "C4", "T20"]