well this at least renders lol

templates/backend.yaml

@@ -1,6 +1,19 @@
 {{- define "vikunja.backend.hardcodedValues" -}}
 global:
-    nameOverride: backend
+  nameOverride: backend
+
+service:
+  main:
+    enabled: true
+    primary: true
+    type: ClusterIP
+    ports:
+      http:
+        enabled: true
+        primary: true
+        port: 3456
+        protocol: HTTP
+
 
 {{ end }}
 

templates/frontend.yaml

@@ -1,8 +1,27 @@
 {{- define "vikunja.frontend.hardcodedValues" -}}
 global:
-    nameOverride: frontend
+  nameOverride: frontend
 
+service:
+  main:
+    enabled: true
+    {{- if not .Values.backend.enabled -}}
+    primary: true
+    {{- end }}
+    type: ClusterIP
+    ports:
+      http:
+        enabled: true
+        {{- if not .Values.backend.enabled -}}
+        primary: true
+        {{- end }}
+        port: 80
+        protocol: HTTP
+        targetPort: 8080
 
+env:
+  - name: VIKUNJA_SERVICE_INTERFACE
+    value: ":8080"
 
 {{ end }}
 

values.yaml

@@ -46,10 +46,17 @@ frontend:
       tls: []
 
 backend:
-  enabled: true
+  enabled: false
   image:
     repository: vikunja/api
     pullPolicy: IfNotPresent
+  persistence:
+    data:
+      enabled: true
+      # existingClaim: # your-claim
+      accessMode: ReadWriteOnce
+      size: 10Gi
+      # storageClass: storage-class
   ingress:
     main:
       enabled: false