diff --git a/.devcontainer/library-scripts/add-deps-redhat.sh b/.devcontainer/library-scripts/add-deps-redhat.sh
index 8a594de5..8fb64235 100644
--- a/.devcontainer/library-scripts/add-deps-redhat.sh
+++ b/.devcontainer/library-scripts/add-deps-redhat.sh
@@ -22,6 +22,7 @@ package_list="\
   openssl-devel \
   gsoap-devel \
   bison \
+  flex \
   gcc-c++"
 
 if ! type git > /dev/null 2>&1; then