diff --git a/build/Dockerfile.buildenv b/build/Dockerfile.buildenv
index f6fb1ef..cdd1563 100644
--- a/build/Dockerfile.buildenv
+++ b/build/Dockerfile.buildenv
@@ -1,5 +1,5 @@
 # rust_icu_buildenv.
-FROM rust:1.71.0 AS buildenv
+FROM rust:1.75.0 AS buildenv
 
 RUN mkdir -p /src
 
diff --git a/build/Makefile b/build/Makefile
index f46de6a..4352b12 100644
--- a/build/Makefile
+++ b/build/Makefile
@@ -93,3 +93,6 @@ latest.stamp: push-buildenv.stamp v74.stamp
 v%.stamp: push-maint-%.stamp push-testenv-%.stamp
 	touch $@
 
+test: tag-maint-74.stamp tag-testenv-74.stamp
+.PHONY: test
+