diff --git a/scripts/check-diff.sh b/scripts/check-diff.sh
new file mode 100755
index 0000000..ec3d5d2
--- /dev/null
+++ b/scripts/check-diff.sh
@@ -0,0 +1,64 @@
+#!/usr/bin/env bash
+
+set -euo pipefail -o nounset
+
+# If the script is run with RUNNER_DEBUG=1, print all statements executed
+if [[ "${RUNNER_DEBUG:-}" == "1" ]]; then
+  set -x
+fi
+
+language="$(jq -r '.github.languages | .[0]' <<< "$CONTEXT")"
+
+default_branch="$(jq -r '.github.default_branch' <<< "$CONTEXT")"
+
+pushd "$TARGET" > /dev/null
+
+actual="$(git diff "origin/$default_branch" | grep '^[+-]')"
+expected=""
+
+if [[ "$language" == "Go" ]]; then
+  expected='--- a/.github/workflows/go-check.yml
++++ b/.github/workflows/go-check.yml
+-    uses: pl-strflt/uci/.github/workflows/go-check.yml@v0.0
++    uses: ipdxco/unified-github-workflows/.github/workflows/go-check.yml@v1.0
+--- a/.github/workflows/go-test.yml
++++ b/.github/workflows/go-test.yml
+-    uses: pl-strflt/uci/.github/workflows/go-test.yml@v0.0
++    uses: ipdxco/unified-github-workflows/.github/workflows/go-test.yml@v1.0
++    secrets:
++      CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}
+--- a/.github/workflows/release-check.yml
++++ b/.github/workflows/release-check.yml
+-    uses: pl-strflt/uci/.github/workflows/release-check.yml@v0.0
++    uses: ipdxco/unified-github-workflows/.github/workflows/release-check.yml@v1.0
+--- a/.github/workflows/releaser.yml
++++ b/.github/workflows/releaser.yml
+-    uses: pl-strflt/uci/.github/workflows/releaser.yml@v0.0
++    uses: ipdxco/unified-github-workflows/.github/workflows/releaser.yml@v1.0
+--- a/.github/workflows/tagpush.yml
++++ b/.github/workflows/tagpush.yml
+-    uses: pl-strflt/uci/.github/workflows/tagpush.yml@v0.0
++    uses: ipdxco/unified-github-workflows/.github/workflows/tagpush.yml@v1.0'
+elif [[ "$language" == "JavaScript" ]]; then
+  expected='--- a/.github/workflows/js-test-and-release.yml
++++ b/.github/workflows/js-test-and-release.yml
++  id-token: write
++  pull-requests: write
+-    uses: pl-strflt/uci/.github/workflows/js-test-and-release.yml@v0.0
++    uses: ipdxco/unified-github-workflows/.github/workflows/js-test-and-release.yml@v1.0
++      CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}'
+else
+  echo "Unknown language: $language"
+  exit 1
+fi
+
+if [[ "$actual" == "$expected" ]]; then
+  echo "No diff found"
+  exit 0
+else
+  echo "Diff found"
+  echo "$actual"
+  echo "---"
+  echo "$expected"
+  exit 1
+fi