diff --git a/apps/matrix-postgresql/cluster/cluster.yaml b/apps/matrix-postgresql/cluster/cluster.yaml
index 6021791..6444ea5 100644
--- a/apps/matrix-postgresql/cluster/cluster.yaml
+++ b/apps/matrix-postgresql/cluster/cluster.yaml
@@ -7,6 +7,9 @@ spec:
   instances: 1
   enableSuperuserAccess: true
   imageName: ghcr.io/cloudnative-pg/postgresql:18.6-standard-trixie
+  postgresql:
+    parameters:
+      max_wal_size: 8GB
   affinity:
     nodeAffinity:
       requiredDuringSchedulingIgnoredDuringExecution: