diff --git a/lib/application.ex b/lib/application.ex
index 714e697..6a27e97 100644
--- a/lib/application.ex
+++ b/lib/application.ex
@@ -4,15 +4,16 @@ defmodule CA do
   that runs TCP and HTTP connections under Erlang/OTP supervision.
   """
   use Application
+  def port(app) do Application.fetch_env!(:ca, app) end
   def start(_type, _args) do
       :logger.add_handlers(:ca)
       Supervisor.start_link([
-         { CA.CMP, port: Application.fetch_env!(:ca, :cmp) },
-         { CA.CMC, port: Application.fetch_env!(:ca, :cmc) },
-         { CA.OCSP, port: Application.fetch_env!(:ca, :ocsp) },
-         { CA.TSP, port: Application.fetch_env!(:ca, :tsp) },
-         { CA.EST, port: Application.fetch_env!(:ca, :est), plug: CA.EST,
-                   scheme: :http, thousand_island_options: [num_acceptors: 1] }
+         { CA.CMP,  port: port(:cmp) },
+         { CA.CMC,  port: port(:cmc) },
+         { CA.OCSP, port: port(:ocsp) },
+         { CA.TSP,  port: port(:tsp) },
+         { CA.EST,  port: port(:est), plug: CA.EST, scheme: :http,
+                    thousand_island_options: [num_acceptors: 1] }
       ], strategy: :one_for_one, name: CA.Supervisor)
   end