diff --git a/.github/workflows/elixir-ci.yml b/.github/workflows/elixir-ci.yml
index b42aac3..fc0e5af 100644
--- a/.github/workflows/elixir-ci.yml
+++ b/.github/workflows/elixir-ci.yml
@@ -58,7 +58,9 @@ jobs:
       run: mix dialyzer
 
     - name: Execute tests
-      run: mix coveralls.json --warnings-as-errors
+      run: |
+        mix test --only integration --warnings-as-errors --max-cases 1 --cover --export-coverage integration-coverage
+        mix coveralls --exclude integration --warnings-as-errors --import-cover cover
 
     - name: Upload coverage report
       run: bash <(curl -s https://codecov.io/bash)
diff --git a/test/config_cat_test.exs b/test/config_cat_test.exs
index 9253e82..4503312 100644
--- a/test/config_cat_test.exs
+++ b/test/config_cat_test.exs
@@ -1,5 +1,8 @@
 defmodule ConfigCatTest do
-  use ConfigCat.ClientCase, async: true
+  # Must be async: false to avoid a collision with other tests.
+  # Now that we only allow a single ConfigCat instance to use the same SDK key,
+  # one of the async tests would fail due to the existing running instance.
+  use ConfigCat.ClientCase, async: false
 
   import ExUnit.CaptureLog
   import Jason.Sigil
diff --git a/test/integration_test.exs b/test/integration_test.exs
index 78b687b..44d5d3d 100644
--- a/test/integration_test.exs
+++ b/test/integration_test.exs
@@ -9,6 +9,8 @@ defmodule ConfigCat.IntegrationTest do
   alias ConfigCat.InMemoryCache
   alias ConfigCat.LocalMapDataSource
 
+  @moduletag :integration
+
   @sdk_key "configcat-sdk-1/PKDVCLf-Hq-h-kCzMp-L7Q/1cGEJXUwYUGZCBOL-E2sOw"
 
   describe "SDK key validation" do