diff --git a/sources/eai-infra/airm-cnpg/0.1.0/templates/cnpg-cluster.yaml b/sources/eai-infra/airm-cnpg/0.1.0/templates/cnpg-cluster.yaml
index 539a08d5..b049a061 100644
--- a/sources/eai-infra/airm-cnpg/0.1.0/templates/cnpg-cluster.yaml
+++ b/sources/eai-infra/airm-cnpg/0.1.0/templates/cnpg-cluster.yaml
@@ -11,7 +11,8 @@ metadata:
 spec:
   affinity:
     enablePodAntiAffinity: true
-    topologyKey: topology.kubernetes.io/zone
+    podAntiAffinityType: {{ .Values.podAntiAffinityType | quote }}
+    topologyKey: {{ .Values.topologyKey | quote }}
   bootstrap:
     initdb:
       database: {{ .Values.database }}
diff --git a/sources/eai-infra/airm-cnpg/0.1.0/values.yaml b/sources/eai-infra/airm-cnpg/0.1.0/values.yaml
index 2e452863..f236fecc 100644
--- a/sources/eai-infra/airm-cnpg/0.1.0/values.yaml
+++ b/sources/eai-infra/airm-cnpg/0.1.0/values.yaml
@@ -7,6 +7,12 @@ database: "airm"
 username: "airm_user"
 image: "ghcr.io/cloudnative-pg/postgresql:17.2"
 instances: 1
+# Spread instances across distinct nodes. "preferred" schedules them apart when
+# nodes allow it and falls back to co-scheduling otherwise, so a cluster with
+# fewer nodes than instances still comes up. Set "required" to make the spread
+# binding, which leaves surplus instances Pending until nodes are added.
+podAntiAffinityType: "preferred"
+topologyKey: "kubernetes.io/hostname"
 userSecretName: "airm-cnpg-user"
 superuserSecretName: "airm-cnpg-superuser"
 sharedBuffers: "256MB"
diff --git a/sources/eai-infra/aiwb-cnpg/0.1.0/templates/cnpg-cluster.yaml b/sources/eai-infra/aiwb-cnpg/0.1.0/templates/cnpg-cluster.yaml
index 539a08d5..b049a061 100644
--- a/sources/eai-infra/aiwb-cnpg/0.1.0/templates/cnpg-cluster.yaml
+++ b/sources/eai-infra/aiwb-cnpg/0.1.0/templates/cnpg-cluster.yaml
@@ -11,7 +11,8 @@ metadata:
 spec:
   affinity:
     enablePodAntiAffinity: true
-    topologyKey: topology.kubernetes.io/zone
+    podAntiAffinityType: {{ .Values.podAntiAffinityType | quote }}
+    topologyKey: {{ .Values.topologyKey | quote }}
   bootstrap:
     initdb:
       database: {{ .Values.database }}
diff --git a/sources/eai-infra/aiwb-cnpg/0.1.0/values.yaml b/sources/eai-infra/aiwb-cnpg/0.1.0/values.yaml
index a6e4fccf..119bac20 100644
--- a/sources/eai-infra/aiwb-cnpg/0.1.0/values.yaml
+++ b/sources/eai-infra/aiwb-cnpg/0.1.0/values.yaml
@@ -7,6 +7,12 @@ database: "aiwb"
 username: "aiwb_user"
 image: "ghcr.io/cloudnative-pg/postgresql:17.2"
 instances: 3
+# Spread instances across distinct nodes. "preferred" schedules them apart when
+# nodes allow it and falls back to co-scheduling otherwise, so a cluster with
+# fewer nodes than instances still comes up. Set "required" to make the spread
+# binding, which leaves surplus instances Pending until nodes are added.
+podAntiAffinityType: "preferred"
+topologyKey: "kubernetes.io/hostname"
 userSecretName: "aiwb-cnpg-user"
 superuserSecretName: "aiwb-cnpg-superuser"
 sharedBuffers: "256MB"
diff --git a/sources/keycloak-config/templates/keycloak-cluster.yaml b/sources/keycloak-config/templates/keycloak-cluster.yaml
index 128e766d..a794a406 100644
--- a/sources/keycloak-config/templates/keycloak-cluster.yaml
+++ b/sources/keycloak-config/templates/keycloak-cluster.yaml
@@ -66,7 +66,8 @@ metadata:
 spec:
   affinity:
     enablePodAntiAffinity: true
-    topologyKey: topology.kubernetes.io/zone
+    podAntiAffinityType: {{ .Values.cnpg.podAntiAffinityType | quote }}
+    topologyKey: {{ .Values.cnpg.topologyKey | quote }}
   bootstrap:
     initdb:
       database: keycloak
diff --git a/sources/keycloak-config/values.yaml b/sources/keycloak-config/values.yaml
index 8f577f31..ca2df535 100644
--- a/sources/keycloak-config/values.yaml
+++ b/sources/keycloak-config/values.yaml
@@ -9,3 +9,9 @@ cnpg:
   # so node maintenance stalls until someone disables it by hand.
   # Set true or false to override.
   enablePDB: null
+  # Spread instances across distinct nodes. "preferred" schedules them apart
+  # when nodes allow it and falls back to co-scheduling otherwise, so a cluster
+  # with fewer nodes than instances still comes up. Set "required" to make the
+  # spread binding, which leaves surplus instances Pending until nodes exist.
+  podAntiAffinityType: "preferred"
+  topologyKey: "kubernetes.io/hostname"