diff --git a/contrib/ci/Dockerfiles/z3_build.Dockerfile b/contrib/ci/Dockerfiles/z3_build.Dockerfile
index 5b9ac9442..562c2dfe5 100644
--- a/contrib/ci/Dockerfiles/z3_build.Dockerfile
+++ b/contrib/ci/Dockerfiles/z3_build.Dockerfile
@@ -52,6 +52,7 @@ ENV \
   USE_OPENMP=${USE_OPENMP} \
   Z3_SRC_DIR=${Z3_SRC_DIR} \
   Z3_BUILD_DIR=/home/user/z3_build \
+  Z3_BUILD_TYPE=${Z3_BUILD_TYPE} \
   Z3_CMAKE_GENERATOR=${Z3_CMAKE_GENERATOR} \
   Z3_VERBOSE_BUILD_OUTPUT=${Z3_VERBOSE_BUILD_OUTPUT} \
   Z3_STATIC_BUILD=${Z3_STATIC_BUILD} \