diff --git a/script/bundle b/script/bundle
index 9c0dddbac4..d1fbeeb9a8 100755
--- a/script/bundle
+++ b/script/bundle
@@ -79,6 +79,11 @@ version_info=$(rustc --version --verbose)
 host_line=$(echo "$version_info" | grep host)
 local_target_triple=${host_line#*: }
 
+if [ -z "$ZED_CLIENT_CHECKSUM_SEED" ]; then
+    echo "Missing ZED_CLIENT_CHECKSUM_SEED environment variable"
+    exit 1
+fi
+
 if [ "$local_arch" = true ]; then
     echo "Building for local target only."
     cargo build ${build_flag} --package ${zed_crate}