diff --git a/src/models/system.coffee b/src/models/system.coffee
new file mode 100644
index 0000000..73bd7c0
--- /dev/null
+++ b/src/models/system.coffee
@@ -0,0 +1,17 @@
+mediator = require '../modules/mediator'
+Model    = require '../utils/model'
+
+# System state.
+system = new Model
+  'data':
+    'loading': no
+
+counter = 0
+async = ->
+  counter += 1
+  system.set 'loading', yes
+  ->
+    counter -= 1
+    system.set 'loading', +counter
+
+module.exports = { system, async }
\ No newline at end of file