diff --git a/.gitea/workflows/scala-test.yml b/.gitea/workflows/scala-test.yml
index 6f087a2..0ec18b7 100644
--- a/.gitea/workflows/scala-test.yml
+++ b/.gitea/workflows/scala-test.yml
@@ -1,5 +1,5 @@
-name: Scala Test
-on: [push]
+name: Scala (sbt) tests
+on: [push, pull_request]
 
 jobs:
   scala-test:
@@ -7,15 +7,44 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
+      # Find an sbt project (first build.sbt found). If none, we skip gracefully.
+      - name: Detect sbt project
+        id: detect
+        shell: bash
+        run: |
+          set -e
+          FILE=$(git ls-files '**/build.sbt' | head -n1 || true)
+          if [ -z "$FILE" ]; then
+            echo "found=false" >> "$GITHUB_OUTPUT"
+            exit 0
+          fi
+          DIR=$(dirname "$FILE")
+          echo "found=true" >> "$GITHUB_OUTPUT"
+          echo "dir=$DIR"   >> "$GITHUB_OUTPUT"
+
       - name: Set up Java (for sbt)
+        if: steps.detect.outputs.found == 'true'
         uses: actions/setup-java@v4
         with:
           distribution: temurin
-          java-version: '11'     # or 17/21 to match your project
-          cache: 'sbt'           # auto-cache Coursier/Ivy for sbt
+          java-version: '11'          # or 17/21 to match your project
+          cache: sbt
+          # Limit cache scan to the detected project to avoid the "no file matched" error
+          cache-dependency-path: |
+            ${{ steps.detect.outputs.dir }}/build.sbt
+            ${{ steps.detect.outputs.dir }}/project/build.properties
+            ${{ steps.detect.outputs.dir }}/project/**/*.scala
+            ${{ steps.detect.outputs.dir }}/project/**/*.sbt
 
       - name: Set up sbt
-        uses: sbt/setup-sbt@v1   # installs sbt
+        if: steps.detect.outputs.found == 'true'
+        uses: sbt/setup-sbt@v1
 
       - name: Run tests
-        run: sbt -batch -v test
\ No newline at end of file
+        if: steps.detect.outputs.found == 'true'
+        working-directory: ${{ steps.detect.outputs.dir }}
+        run: sbt -batch -v test
+
+      - name: Skip (no sbt project found)
+        if: steps.detect.outputs.found != 'true'
+        run: echo "No sbt project found; skipping Scala tests."