diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 52e4bd8..fc00783 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -188,10 +188,23 @@ jobs:
           echo "LD_LIBRARY_PATH=$LP:${LD_LIBRARY_PATH:-}" >> $GITHUB_ENV
 
       #######################   Setup Python   #######################
+      # detect python version from SOFA binaries instead of hardcoding it.
+      - name: Detect SOFA python version
+        id: pyver
+        shell: bash
+        run: |
+          set -euo pipefail
+          SP="$SOFA_ROOT/plugins/SofaPython3/lib/python3/site-packages/Sofa"
+          TAG=$(ls "$SP" | grep -oE '^Helper\.(cpython-|cp)3[0-9]+' | grep -oE '3[0-9]+$' | head -n1)
+          [[ -n "$TAG" ]] || { echo "::error::Could not detect python ABI tag from $SP"; ls -la "$SP"; exit 1; }
+          VERSION="3.${TAG:1}"
+          echo "SOFA was built against python $VERSION"
+          echo "version=$VERSION" >> $GITHUB_OUTPUT
+
       - name: Setup Python
         uses: actions/setup-python@v5
         with:
-          python-version: '3.10'
+          python-version: ${{ steps.pyver.outputs.version }}
 
       - name: Install dependencies
         shell: bash
@@ -231,6 +244,11 @@ jobs:
 
       - name: Run regression
         shell: bash
+        env:
+          # The regression program captures each scene's output with
+          # subprocess.run(text=True), which decodes with the locale encoding:
+          # cp1252 on Windows, which chokes on SOFA's UTF-8 logs.
+          PYTHONUTF8: '1'
         run: |
           set -euo pipefail
           cd "$WORKSPACE_SRC_PATH"