diff --git a/lib/package/macos.ex b/lib/package/macos.ex
index 8eb5250..a2ce420 100644
--- a/lib/package/macos.ex
+++ b/lib/package/macos.ex
@@ -690,6 +690,8 @@ defmodule Desktop.Deployment.Package.MacOS do
   end
 
   defp uid_to_string(uid) when is_list(uid), do: List.to_string(uid)
+  # DirectoryString as decoded by :public_key, e.g. {:utf8String, "..."}
+  defp uid_to_string({_type, uid}), do: uid_to_string(uid)
   defp uid_to_string(uid), do: to_string(uid)
 
   def maybe_import_p12(file, password, uids, keychain_password \\ nil) do
@@ -796,7 +798,7 @@ defmodule Desktop.Deployment.Package.MacOS do
   end
 
   defp scan({:AttributeTypeAndValue, @friendly_attribute, friendly}) do
-    case Regex.scan(~r/\(([^)]+)\)$/, friendly) do
+    case Regex.scan(~r/\(([^)]+)\)$/, uid_to_string(friendly)) do
       [[_full, uid]] -> [uid]
       _ -> []
     end
diff --git a/mix.exs b/mix.exs
index e53244d..faabf56 100644
--- a/mix.exs
+++ b/mix.exs
@@ -38,11 +38,11 @@ defmodule Desktop.Deployment.MixProject do
   defp deps do
     [
       # Credo
-      {:httpoison, "~> 2.0", runtime: false},
+      {:httpoison, "~> 3.0", runtime: false},
       {:credo, "~> 1.5", only: [:dev, :test], runtime: false},
       # 1.3.0+ (icon embedding) is on GitHub; switch to Hex once published.
       {:libpe, github: "elixir-desktop/libpe", branch: "master"},
-      {:poison, "~> 3.0"}
+      {:poison, "~> 6.0"}
     ]
   end
 end
diff --git a/test/codesign_test.exs b/test/codesign_test.exs
index 2b3e9f9..8fd6c81 100644
--- a/test/codesign_test.exs
+++ b/test/codesign_test.exs
@@ -1,6 +1,8 @@
 defmodule CodesignTest do
   use ExUnit.Case
 
+  @moduletag :macos
+
   test "codesign a new binary" do
     {_, 0} = System.cmd("gcc", ["test/priv/main.c", "-o", "unsigned_main"])
     Desktop.Deployment.Package.MacOS.codesign_executable("unsigned_main")
diff --git a/test/test_helper.exs b/test/test_helper.exs
index 869559e..4397083 100644
--- a/test/test_helper.exs
+++ b/test/test_helper.exs
@@ -1 +1,2 @@
-ExUnit.start()
+exclude = if match?({:unix, :darwin}, :os.type()), do: [], else: [:macos]
+ExUnit.start(exclude: exclude)