diff --git a/public/v4/apps/ohmyform.yml b/public/v4/apps/ohmyform.yml
index 3182388..fd7acf8 100644
--- a/public/v4/apps/ohmyform.yml
+++ b/public/v4/apps/ohmyform.yml
@@ -1,45 +1,48 @@
 captainVersion: 4
 services:
     $$cap_appname-redis:
-        image: redis
+        image: redis:6.0
         caproverExtra:
             notExposeAsWebApp: 'true'
-    $$cap_appname-mongo:
-        image: mongo
+    $$cap_appname-pg:
+        image: postgres:10-alpine
         volumes:
-            - $$cap_appname-mongo-data:/data/db
+            - $$cap_appname-mongo-data:/var/lib/postgresql/data
         environment:
-            MONGO_INITDB_ROOT_USERNAME: $$cap_db_user
-            MONGO_INITDB_ROOT_PASSWORD: $$cap_db_pass
+            POSTGRES_USER: root
+            POSTGRES_DB: $$cap_db_pass
+            MONGO_INITDB_ROOT_PASSWORD: ohmyform
         caproverExtra:
             notExposeAsWebApp: 'true'
     $$cap_appname-mailhog:
-        image: mailhog/mailhog
+        image: mailhog/mailhog:v1.0.1
         caproverExtra:
             notExposeAsWebApp: 'true'
+    $$cap_appname:
+        image: ohmyform/ui:0.9.9
+        environment:
+            ENDPOINT: https://$$cap_appname-api.$$cap_root_domain/graphql
+            SERVER_ENDPOINT: https://$$cap_appname-api.$$cap_root_domain/graphql
+            HIDE_CONTRIB: true
+            APP_NAME: $$cap_ohmyform_title
+            PORT: 5000
+        caproverExtra:
+            containerHttpPort: '5000'
     $$cap_appname-api:
-        image: ohmyform/api
+        image: ohmyform/api:0.9.9
         environment:
             CREATE_ADMIN: true
             ADMIN_EMAIL: $$cap_ohmyform_email
             ADMIN_USERNAME: $$cap_ohmyform_user
             ADMIN_PASSWORD: $$cap_ohmyform_pass
-            MONGODB_URI: mongodb://$$cap_db_user:$$cap_db_pass@srv-captain--$$cap_appname-mongo:27017/$$cap_appname?authSource=admin
+            DATABASE_DRIVER: postgres
+            DATABASE_URL: postgresql://root:$$cap_db_pass@srv-captain--$$cap_appname-pg:5432/ohmyform
             MAILER_URI: smtp://srv-captain--$$cap_appname-mailhog:1025
             REDIS_URL: redis://$$cap_appname-redis
             SECRET_KEY: $$cap_gen_random_hex(64)
             PORT: 5000
         caproverExtra:
             containerHttpPort: '5000'
-    $$cap_appname:
-        image: ohmyform/ui
-        environment:
-            API_HOST: https://$$cap_appname-api.$$cap_root_domain/graphql
-            HIDE_CONTRIB: true
-            APP_NAME: $$cap_ohmyform_title
-            PORT: 5000
-        caproverExtra:
-            containerHttpPort: '5000'
 caproverOneClickApp:
     variables:
         - id: $$cap_ohmyform_email
@@ -56,10 +59,6 @@ caproverOneClickApp:
           description: Password for the OhMyForm admin user
           defaultValue: $$cap_gen_random_hex(64)
           validRegex: /.{1,}/
-        - id: $$cap_db_user
-          label: Database user
-          defaultValue: ohmyform
-          validRegex: /^([a-zA-Z0-9])+$/
         - id: $$cap_db_pass
           label: Database password
           defaultValue: $$cap_gen_random_hex(64)