diff --git a/apps/explorer/mix.exs b/apps/explorer/mix.exs
index b5f75ef64a..ad7659c8b5 100644
--- a/apps/explorer/mix.exs
+++ b/apps/explorer/mix.exs
@@ -11,7 +11,7 @@ defmodule Explorer.Mixfile do
       deps_path: "../../deps",
       dialyzer: [
         plt_add_deps: :transitive,
-        plt_add_apps: [:mix],
+        plt_add_apps: ~w(ex_unit mix)a,
         ignore_warnings: "../../.dialyzer-ignore"
       ],
       elixir: "~> 1.6",
diff --git a/mix.exs b/mix.exs
index c8e4a3e43f..ff0723faca 100644
--- a/mix.exs
+++ b/mix.exs
@@ -10,7 +10,7 @@ defmodule ExplorerUmbrella.Mixfile do
       deps: deps(),
       dialyzer: [
         plt_add_deps: :transitive,
-        plt_add_apps: [:mix],
+        plt_add_apps: ~w(ex_unit mix)a,
         ignore_warnings: ".dialyzer-ignore"
       ],
       elixir: "~> 1.6",