diff --git a/dockerfile b/dockerfile
index e9d0702..016619b 100644
--- a/dockerfile
+++ b/dockerfile
@@ -2,14 +2,14 @@
 #
 # SPDX-License-Identifier: AGPL-3.0-or-later
 
-FROM debian:stable-slim
+FROM debian:bullseye-slim
 
 ARG DEBIAN_FRONTEND=noninteractive
 ARG GIT_COMMIT
 ARG VERSION
 ARG TIMESTAMP
 LABEL org.opencontainers.image.licenses="AGPL-3.0-or-later" \
-org.opencontainers.image.base.name="docker.io/debian:stable-slim" \
+org.opencontainers.image.base.name="docker.io/debian:bullseye-slim" \
 org.opencontainers.image.title=buildimage \
 org.opencontainers.image.source="https://git.schmidl.dev/schtobia/buildimage" \
 org.opencontainers.image.url="https://git.schmidl.dev/schtobia/buildimage"
@@ -21,6 +21,7 @@ LABEL org.opencontainers.image.created=${TIMESTAMP}
 RUN apt update \
  && apt install --assume-yes --no-install-recommends \
         build-essential \
+        dpkg-sig \
         git \
  && find /var/lib/apt -type f -delete