diff --git a/podman-matrix/ci_build-images.sh b/podman-matrix/ci_build-images.sh
index 5ad7659..ffde53b 100755
--- a/podman-matrix/ci_build-images.sh
+++ b/podman-matrix/ci_build-images.sh
@@ -9,11 +9,13 @@ ensure_not_root
 
 buildfolder=/tmp/synapse-$$
 
+buildkitd_version='v0.11.6' # latest v0.12.0 is broken
+
 if ! podman image exists ${synapse_image}:${synapse_version}; then
     mkdir ${buildfolder} &&
     curl -sSfL -- "https://github.com/matrix-org/synapse/archive/refs/tags/${synapse_version}.tar.gz" | \tar xz --strip-components 1 -C ${buildfolder}/ && {
-        podman image pull docker.io/moby/buildkit:latest
-        podman container run -d --name buildkitd --privileged docker.io/moby/buildkit:latest &&
+        podman image pull docker.io/moby/buildkit:${buildkitd_version}
+        podman container run -d --name buildkitd --privileged docker.io/moby/buildkit:${buildkitd_version} &&
         my_buildctl --addr=podman-container://buildkitd build \
 		       --frontend dockerfile.v0 \
 		       --local context=${buildfolder}/ \
@@ -21,7 +23,7 @@ if ! podman image exists ${synapse_image}:${synapse_version}; then
 		       --output type=oci,name="${synapse_image}:${synapse_version}" | \
                        podman image load &&
 	podman container rm --force buildkitd &&
-	podman image rm docker.io/moby/buildkit:latest
+	podman image rm docker.io/moby/buildkit:${buildkitd_version}
     }
     rm -rf ${buildfolder}
 else