diff --git a/lib/xlsxir.ex b/lib/xlsxir.ex
index a41883a..03fa492 100644
--- a/lib/xlsxir.ex
+++ b/lib/xlsxir.ex
@@ -4,10 +4,9 @@ defmodule Xlsxir do
   use Application
 
   def start(_type, _args) do
-    import Supervisor.Spec
 
     children = [
-      worker(Xlsxir.StateManager, [])
+      %{id: Xlsxir.StateManager, start: {Xlsxir.StateManager, :start_link, []}, type: :worker}
     ]
 
     opts = [strategy: :one_for_one, name: __MODULE__]
diff --git a/mix.exs b/mix.exs
index a1172d5..dbac462 100644
--- a/mix.exs
+++ b/mix.exs
@@ -20,7 +20,7 @@ defmodule Xlsxir.Mixfile do
   def application do
     [
       mod: {Xlsxir, []},
-      extra_applications: [:logger]
+      extra_applications: [:logger, :crypto]
     ]
   end