diff --git a/.github/workflows/build-wheels.yaml b/.github/workflows/build-wheels.yaml
index d8f3f45..7f30795 100644
--- a/.github/workflows/build-wheels.yaml
+++ b/.github/workflows/build-wheels.yaml
@@ -17,7 +17,7 @@ jobs:
 
     steps:
       - name: "Checkout repo"
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: "Build wheels"
         uses: pypa/cibuildwheel@v2.8.1
@@ -37,7 +37,7 @@ jobs:
           # CIBW_TEST_COMMAND: "pytest {project}/tests"
 
       - name: "Upload wheel as artifact"
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: artifact-${{ matrix.os }}-wheel
           path: "./**/*.whl"
@@ -46,11 +46,11 @@ jobs:
     name: Make source distribution
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
 
     - run: pipx run build --sdist
 
-    - uses: actions/upload-artifact@v3
+    - uses: actions/upload-artifact@v4
       with:
         name: artifact-source-dist
         path: "./**/dist/*.tar.gz"
@@ -64,7 +64,7 @@ jobs:
     if: github.event_name == 'release' && github.event.action == 'published'
     steps:
     - name: Download all artifacts
-      uses: actions/download-artifact@v3
+      uses: actions/download-artifact@v4
 
     - name: Copy artifacts to dist/ folder
       run: |
diff --git a/.github/workflows/documentation.yaml b/.github/workflows/documentation.yaml
index 27360fd..99ac990 100644
--- a/.github/workflows/documentation.yaml
+++ b/.github/workflows/documentation.yaml
@@ -11,8 +11,8 @@ jobs:
   docs:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
-      - uses: actions/setup-python@v3
+      - uses: actions/checkout@v4
+      - uses: actions/setup-python@v5
       - name: Install cmdstanpy
         run: |
           python -m pip install --upgrade pip wheel
diff --git a/.github/workflows/main.yaml b/.github/workflows/main.yaml
index cc44edf..4e2e13e 100644
--- a/.github/workflows/main.yaml
+++ b/.github/workflows/main.yaml
@@ -22,14 +22,14 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest]  # , macos-latest, windows-latest
-        python-version: ["3.10"]  # 3.7, 3.8, 3.9, 
+        python-version: ["3.10", "3.11"]  # 3.7, 3.8, 3.9, 
     env:
       GITHUB_PAT: ${{ secrets.GITHUB_TOKEN }}
     steps:
       - name: Check out github
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
       - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v2
+        uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python-version }}
       - name: Install cmdstanpy