diff --git a/.bazelversion b/.bazelversion
new file mode 100644
index 0000000..a083f68
--- /dev/null
+++ b/.bazelversion
@@ -0,0 +1,2 @@
+7.4.1
+# make sure that the image in the Dockerfile and this version are identical
diff --git a/Dockerfile b/Dockerfile
index e277882..7cc2119 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,5 @@
 FROM gcr.io/bazel-public/bazel:7.4.1 AS builder
+# Make sure .bazelversion and the version of image are identical
 
 WORKDIR /wgkex