Let's try this pattern for app config. Refactor postgres.

apps/postgres/config/kustomization.yaml

@@ -0,0 +1,18 @@
+apiVersion: kustomize.config.k8s.io/v1beta1
+kind: Kustomization
+namespace: postgres
+labels:
+  - includeSelectors: true
+    pairs:
+      app: postgres
+      managedBy: kustomize
+      partOf: wild-cloud
+
+configMapGenerator:
+  - name: config
+    envs:
+      - config.env
+secretGenerator:
+  - name: secrets
+    envs:
+      - secrets.env