diff --git a/config/settings.yml b/config/settings.yml
index f9a1ae1d8..58061e29c 100644
--- a/config/settings.yml
+++ b/config/settings.yml
@@ -197,6 +197,8 @@ session-memcached:
   timeout:    "_env:SESSION_MEMCACHED_TIMEOUT:20"
   expiration: "_env:SESSION_MEMCACHED_EXPIRATION:28807"
 
+
+# TODO: this one seems to be required!
 memcached:
   host:       "_env:MEMCACHED_HOST:localhost"
   port:       "_env:MEMCACHED_PORT:11211"
@@ -210,10 +212,10 @@ memcached-local:
   maximum-weight: 104857600 # 100MiB
 
 upload-cache:
-  host: "_env:UPLOAD_S3_HOST:" # should be optional, but all file transfers will be empty without an S3 cache
+  host: "_env:UPLOAD_S3_HOST:localhost" # should be optional, but all file transfers will be empty without an S3 cache
   port: "_env:UPLOAD_S3_PORT:9000"
-  access-key: "_env:UPLOAD_S3_KEY_ID:"
-  secret-key: "_env:UPLOAD_S3_KEY"
+  access-key: "_env:UPLOAD_S3_KEY_ID:minioadmin"
+  secret-key: "_env:UPLOAD_S3_KEY:minioadmin"
   is-secure: "_env:UPLOAD_S3_SSL:false"
   region: "_env:UPLOAD_S3_REGION:"
   auto-discover-region: "_env:UPLOAD_S3_AUTO_DISCOVER_REGION:true"