diff --git a/test/chronoscope/nts/certificate_test.exs b/test/chronoscope/nts/certificate_test.exs
index 1f1b95c..f7fa187 100644
--- a/test/chronoscope/nts/certificate_test.exs
+++ b/test/chronoscope/nts/certificate_test.exs
@@ -1,5 +1,5 @@
 defmodule Chronoscope.NTS.CertificateTest do
-  use Chronoscope.Case
+  use Chronoscope.Case, async: true
 
   alias Chronoscope.NTS.DateTimeMock
 
diff --git a/test/chronoscope/nts/client_test.exs b/test/chronoscope/nts/client_test.exs
index 55a6e00..7d347c3 100644
--- a/test/chronoscope/nts/client_test.exs
+++ b/test/chronoscope/nts/client_test.exs
@@ -1,5 +1,5 @@
 defmodule Chronoscope.NTS.ClientTest do
-  use Chronoscope.Case
+  use Chronoscope.Case, async: true
 
   alias Chronoscope.NTS.Certificate
   alias Chronoscope.NTS.DateTimeMock
diff --git a/test/chronoscope/nts/key_establishment_client_test.exs b/test/chronoscope/nts/key_establishment_client_test.exs
index 2f58c72..bbabe55 100644
--- a/test/chronoscope/nts/key_establishment_client_test.exs
+++ b/test/chronoscope/nts/key_establishment_client_test.exs
@@ -1,5 +1,5 @@
 defmodule Chronoscope.NTS.KeyEstablishmentClientTest do
-  use Chronoscope.Case
+  use Chronoscope.Case, async: true
 
   alias Chronoscope.NTS.Certificate
   alias Chronoscope.NTS.KeyEstablishmentRequest
diff --git a/test/chronoscope/nts/key_establishment_request_test.exs b/test/chronoscope/nts/key_establishment_request_test.exs
index 671eb86..bc1beb0 100644
--- a/test/chronoscope/nts/key_establishment_request_test.exs
+++ b/test/chronoscope/nts/key_establishment_request_test.exs
@@ -1,5 +1,5 @@
 defmodule Chronoscope.NTS.KeyEstablishmentRequestTest do
-  use Chronoscope.Case
+  use Chronoscope.Case, async: true
 
   import Chronoscope.NTS.KeyEstablishmentRequest
 
diff --git a/test/chronoscope/nts/key_establishment_response_test.exs b/test/chronoscope/nts/key_establishment_response_test.exs
index 85e8673..03b2a3f 100644
--- a/test/chronoscope/nts/key_establishment_response_test.exs
+++ b/test/chronoscope/nts/key_establishment_response_test.exs
@@ -1,5 +1,5 @@
 defmodule Chronoscope.NTS.KeyEstablishmentResponseTest do
-  use Chronoscope.Case
+  use Chronoscope.Case, async: true
 
   import Chronoscope.NTS.KeyEstablishmentResponse
 
diff --git a/test/chronoscope/nts_test.exs b/test/chronoscope/nts_test.exs
index 54aeab6..f7ec5dd 100644
--- a/test/chronoscope/nts_test.exs
+++ b/test/chronoscope/nts_test.exs
@@ -1,5 +1,5 @@
 defmodule Chronoscope.NTSTest do
-  use Chronoscope.Case
+  use Chronoscope.Case, async: true
 
   alias Chronoscope.NTS
   alias Chronoscope.NTS.DynamicSupervisorMock
diff --git a/test/chronoscope_web/controllers/page_controller_test.exs b/test/chronoscope_web/controllers/page_controller_test.exs
index b3f7c47..e11c7c9 100644
--- a/test/chronoscope_web/controllers/page_controller_test.exs
+++ b/test/chronoscope_web/controllers/page_controller_test.exs
@@ -1,5 +1,5 @@
 defmodule ChronoscopeWeb.PageControllerTest do
-  use ChronoscopeWeb.ConnCase
+  use ChronoscopeWeb.ConnCase, async: true
 
   test "GET /", %{conn: conn} do
     conn = get(conn, ~p"/")