diff --git a/app/matrix/lib/matrix.libsonnet b/app/matrix/lib/matrix.libsonnet
index dbf27d9..d13d620 100644
--- a/app/matrix/lib/matrix.libsonnet
+++ b/app/matrix/lib/matrix.libsonnet
@@ -85,6 +85,7 @@
     postgres3: ns.Contain(postgres) {
         cfg+: {
             appName: "synapse",
+            version: "10.4",
             database: "synapse",
             username: "synapse",
             prefix: "waw3-",