diff --git a/deploy/production/build-frontend.sh b/deploy/production/build-frontend.sh
index 9daeb54..5a7408c 100755
--- a/deploy/production/build-frontend.sh
+++ b/deploy/production/build-frontend.sh
@@ -4,9 +4,9 @@ set -euo pipefail
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 REPO_DIR="$(cd "$SCRIPT_DIR/../.." && pwd)"
 FRONTEND_DIR="$REPO_DIR/frontend"
-SOURCE_GIT_FULL_SHA="$(git -C "$REPO_DIR" rev-parse HEAD)"
-SOURCE_GIT_SHA="$(git -C "$REPO_DIR" rev-parse --short HEAD)"
-SOURCE_GIT_REF="$(git -C "$REPO_DIR" branch --show-current 2>/dev/null || true)"
+SOURCE_GIT_FULL_SHA="$(cd "$REPO_DIR" && git rev-parse HEAD)"
+SOURCE_GIT_SHA="$(cd "$REPO_DIR" && git rev-parse --short HEAD)"
+SOURCE_GIT_REF="$(cd "$REPO_DIR" && git symbolic-ref --quiet --short HEAD 2>/dev/null || true)"
 SOURCE_GIT_REF="${SOURCE_GIT_REF:-main}"
 
 test -f "$FRONTEND_DIR/package-lock.json" || {