diff --git a/swh/web/ui/main.py b/swh/web/ui/main.py
index 4cdd16bf..e7aa8a4b 100644
--- a/swh/web/ui/main.py
+++ b/swh/web/ui/main.py
@@ -1,134 +1,126 @@
 # Copyright (C) 2015  The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU Affero General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
 import logging
 import os
 
-# from flask import Flask
-from flask.ext.api import FlaskAPI, renderers
-# from flask.ext.api import renderers
-import yaml
+from flask.ext.api import FlaskAPI
 
 from swh.core import config
 
 
 DEFAULT_CONFIG = {
     'storage_args': ('list[str]', ['http://localhost:5000/']),
     'storage_class': ('str', 'remote_storage'),
     'log_dir': ('string', '/tmp/swh/log'),
     'debug': ('bool', None),
     'host': ('string', '127.0.0.1'),
     'port': ('int', 6543),
     'secret_key': ('string', 'development key'),
     'max_upload_size': ('int', 16 * 1024 * 1024),
     'upload_folder': ('string', '/tmp/swh-web-ui/uploads'),
     'upload_allowed_extensions': ('list[str]', [])  # means all are accepted
 }
 
 
 # api's definition
-# app = Flask(__name__)
 app = FlaskAPI(__name__)
 
 
-
-class YAMLRenderer(renderers.BaseRenderer):
-    media_type = 'application/yaml'
-
-    def render(self, data, media_type, **options):
-        return yaml.dump(data, encoding=self.charset)
-
-app.config['DEFAULT_RENDERERS'] = [
-    'flask.ext.api.renderers.JSONRenderer',
-    'flask.ext.api.renderers.BrowsableAPIRenderer',
-    'swh.web.ui.main.YAMLRenderer'
-]
-
-
 def read_config(config_file):
     """Read the configuration file `config_file`, update the app with
        parameters (secret_key, conf) and return the parsed configuration as a
        dict"""
 
     conf = config.read(config_file, DEFAULT_CONFIG)
     config.prepare_folders(conf, 'log_dir')
 
     if conf['storage_class'] == 'remote_storage':
         from swh.storage.api.client import RemoteStorage as Storage
     else:
         from swh.storage import Storage
 
     conf['storage'] = Storage(*conf['storage_args'])
 
     return conf
 
 
 def load_controllers():
     """Load the controllers for the application"""
     from swh.web.ui import controller  # flake8: noqa
 
 
 def storage():
     """Return the current application's storage.
 
     """
     return app.config['conf']['storage']
 
 
 def run_from_webserver(environ, start_response):
     """Run the WSGI app from the webserver, loading the configuration."""
 
     load_controllers()
 
     config_path = '/etc/softwareheritage/webapp/webapp.ini'
 
     conf = read_config(config_path)
 
     app.secret_key = conf['secret_key']
     app.config['conf'] = conf
     app.config['MAX_CONTENT_LENGTH'] = conf['max_upload_size']
+    app.config['DEFAULT_RENDERERS'] = [
+        'flask.ext.api.renderers.JSONRenderer',
+        'flask.ext.api.renderers.BrowsableAPIRenderer',
+        'swh.web.ui.renderers.YAMLRenderer'
+    ]
 
     logging.basicConfig(filename=os.path.join(conf['log_dir'], 'web-ui.log'),
                         level=logging.INFO)
 
     return app(environ, start_response)
 
 
 def run_debug_from(config_path, verbose=False):
     """Run the api's server in dev mode.
 
     Args:
         conf is a dictionary of keywords:
         - 'db_url' the db url's access (through psycopg2 format)
         - 'content_storage_dir' revisions/directories/contents storage on disk
         - 'host'   to override the default 127.0.0.1 to open or not the server
         to the world
         - 'port'   to override the default of 5000 (from the underlying layer:
         flask)
         - 'debug'  activate the verbose logs
         - 'secret_key' the flask secret key
 
     Returns:
         Never
 
     """
     load_controllers()
 
     conf = read_config(config_path)
 
     app.secret_key = conf['secret_key']
     app.config['conf'] = conf
     app.config['MAX_CONTENT_LENGTH'] = conf['max_upload_size']
+    app.config['DEFAULT_RENDERERS'] = [
+        'flask.ext.api.renderers.JSONRenderer',
+        'flask.ext.api.renderers.BrowsableAPIRenderer',
+        'swh.web.ui.renderers.YAMLRenderer'
+    ]
 
     host = conf.get('host', '127.0.0.1')
     port = conf.get('port')
     debug = conf.get('debug')
 
     log_file = os.path.join(conf['log_dir'], 'web-ui.log')
     logging.basicConfig(level=logging.DEBUG if verbose else logging.INFO,
                         handlers=[logging.FileHandler(log_file),
                                   logging.StreamHandler()])
 
     app.run(host=host, port=port, debug=debug)
diff --git a/swh/web/ui/renderers.py b/swh/web/ui/renderers.py
new file mode 100644
index 00000000..2079a4ec
--- /dev/null
+++ b/swh/web/ui/renderers.py
@@ -0,0 +1,15 @@
+# Copyright (C) 2015  The Software Heritage developers
+# See the AUTHORS file at the top-level directory of this distribution
+# License: GNU Affero General Public License version 3, or any later version
+# See top-level LICENSE file for more information
+
+
+from flask.ext.api import renderers
+import yaml
+
+
+class YAMLRenderer(renderers.BaseRenderer):
+    media_type = 'application/yaml'
+
+    def render(self, data, media_type, **options):
+        return yaml.dump(data, encoding=self.charset)