diff --git a/.gitlab-ci/Dockerfile b/.gitlab-ci/Dockerfile
index 40c5e76ea68481ca7bcf914a6dcc601f5ce36542..a7ebaf7b256e7a74e9956e7e4f8f66c7cd7ac407 100644
--- a/.gitlab-ci/Dockerfile
+++ b/.gitlab-ci/Dockerfile
@@ -1,4 +1,4 @@
-FROM debian:buster
+FROM debian:bullseye
 
 ENV LANG C.UTF-8
 ENV DEBIAN_FRONTEND noninteractive