diff --git a/config/00-main.yaml b/config/00-main.yaml
index 6c11c7e1..ec840af8 100644
--- a/config/00-main.yaml
+++ b/config/00-main.yaml
@@ -63,9 +63,10 @@ scoring_systems:
     queue_maxsize: 100 # pending tasks
     broker_url: redis://localhost
     broker_transport_options: {'socket_timeout': 15} # seconds
-    accept_content: ['pickle']
+    accept_content:
+      - 'pickle'
     task_serializer: 'pickle'
-    result_serialize: 'pickle'
+    result_serializer: 'pickle'
     result_backend: redis://localhost
     worker_concurrency: 8
     worker_hijack_root_logger: false
diff --git a/requirements.txt b/requirements.txt
index f930e1f3..6053e82f 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -7,6 +7,7 @@ flask-wikimediaui >= 0.0.1, < 0.0.999
 mwapi >= 0.5.0, < 0.5.999
 pytest >= 3.2.2, < 3.2.999
 pyyaml == 3.11
+redis >= 2.10.6, < 3.0.0
 revscoring >= 2.2.2, < 2.2.999
 sseclient >= 0.0.18
 stopit >= 1.1.1, < 1.1.999