diff --git a/.github/workflows/phpcs.yml b/.github/workflows/phpcs.yml
index ab91115..ec1dc0b 100644
--- a/.github/workflows/phpcs.yml
+++ b/.github/workflows/phpcs.yml
@@ -78,27 +78,27 @@ jobs:
         env:
           REVIEWDOG_GITHUB_API_TOKEN: ${{ secrets.access-token }}
         run: |
-          # Read changed files into array - preserves filenames with spaces, avoids xargs exit code translation
           mapfile -t FILES <<< "${{ env.CHANGED_FILES }}"
 
-          # Run phpcs - || captures real exit code without letting bash -e kill the step early
-          PHPCS_EXIT_CODE=0
-          JSON_REPORT=$(vendor/bin/phpcs --report=json -q "${FILES[@]}") || PHPCS_EXIT_CODE=$?
+          # phpcs's exit code covers the whole file (incl. pre-existing issues on
+          # untouched lines), so it must not gate the job. set +e stops bash -e
+          # from killing the step on that non-zero exit.
+          set +e
+          CHECKSTYLE_REPORT=$(vendor/bin/phpcs --report=checkstyle -q "${FILES[@]}")
+          PHPCS_EXIT_CODE=$?
+          set -e
 
-          # Check if phpcs produced a JSON report
-          if [ -z "$JSON_REPORT" ]; then
-            echo "No JSON report generated by phpcs"
-            exit $PHPCS_EXIT_CODE
+          # No report + non-zero exit means phpcs itself failed to run.
+          if [ -z "$CHECKSTYLE_REPORT" ] && [ "$PHPCS_EXIT_CODE" -ne 0 ]; then
+            echo "phpcs failed to run (exit code $PHPCS_EXIT_CODE)"
+            exit "$PHPCS_EXIT_CODE"
           fi
 
-          # Validate the JSON
-          if ! echo "$JSON_REPORT" | jq empty; then
-            echo "Invalid JSON"
-            exit 1
-          fi
-
-          # Process JSON and run reviewdog
-          echo "$JSON_REPORT" | jq -r ' .files | to_entries[] | .key as $path | .value.messages[] as $msg | "\($path):\($msg.line):\($msg.column):`\($msg.source)`<br>\($msg.message)" ' | reviewdog -efm="%f:%l:%c:%m" -name="phpcs" -filter-mode="added" -fail-level=any -reporter=github-pr-review
+          # reviewdog gates the job: -filter-mode=added + -fail-level=any make it
+          # exit 1 only for violations on lines this PR changed.
+          REVIEWDOG_EXIT_CODE=0
+          echo "$CHECKSTYLE_REPORT" \
+            | reviewdog -f=checkstyle -name="phpcs" -filter-mode="added" -fail-level=any -reporter=github-pr-review \
+            || REVIEWDOG_EXIT_CODE=$?
 
-          # Exit with the original phpcs exit code
-          exit $PHPCS_EXIT_CODE
+          exit "$REVIEWDOG_EXIT_CODE"