diff --git a/changelog.d/17389.misc b/changelog.d/17389.misc
new file mode 100644
index 000000000..7022ed93d
--- /dev/null
+++ b/changelog.d/17389.misc
@@ -0,0 +1 @@
+Fix building debian package for debian sid.
diff --git a/docker/Dockerfile-dhvirtualenv b/docker/Dockerfile-dhvirtualenv
index b7679924c..f00014456 100644
--- a/docker/Dockerfile-dhvirtualenv
+++ b/docker/Dockerfile-dhvirtualenv
@@ -73,6 +73,8 @@ RUN apt-get update -qq -o Acquire::Languages=none \
     curl \
     debhelper \
     devscripts \
+    # Required for building cffi from source.
+    libffi-dev \
     libsystemd-dev \
     lsb-release \
     pkg-config \