diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index b9f9188..88ba8f6 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -10,28 +10,34 @@ jobs:
       matrix:
         # https://hexdocs.pm/elixir/compatibility-and-deprecations.html
         include:
-          - elixir-version: 1.17.x
-            otp-version: 27.x
-          - elixir-version: 1.17.x
-            otp-version: 26.x
-          - elixir-version: 1.17.x
-            otp-version: 25.x
-          - elixir-version: 1.16.x
-            otp-version: 26.x
-          - elixir-version: 1.16.x
-            otp-version: 25.x
-          - elixir-version: 1.15.x
-            otp-version: 26.x
-          - elixir-version: 1.15.x
-            otp-version: 25.x
-          - elixir-version: 1.14.x
-            otp-version: 25.x
-          - elixir-version: 1.13.x
-            otp-version: 24.x
+          - elixir-version: "1.18"
+            otp-version: "27"
+          - elixir-version: "1.18"
+            otp-version: "26"
+          - elixir-version: "1.18"
+            otp-version: "25"
+          - elixir-version: "1.17"
+            otp-version: "27"
+          - elixir-version: "1.17"
+            otp-version: "26"
+          - elixir-version: "1.17"
+            otp-version: "25"
+          - elixir-version: "1.16"
+            otp-version: "26"
+          - elixir-version: "1.16"
+            otp-version: "25"
+          - elixir-version: "1.15"
+            otp-version: "26"
+          - elixir-version: "1.15"
+            otp-version: "25"
+          - elixir-version: "1.14"
+            otp-version: "25"
+          - elixir-version: "1.13"
+            otp-version: "24"
     env:
       MIX_ENV: test
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: erlef/setup-beam@v1
         with:
           otp-version: ${{ matrix.otp-version }}
diff --git a/config/config.exs b/config/config.exs
index 7373480..d1f013c 100644
--- a/config/config.exs
+++ b/config/config.exs
@@ -1,34 +1,5 @@
-# This file is responsible for configuring your application
-# and its dependencies with the aid of the Mix.Config module.
-use Mix.Config
+import Config
 
 config :absinthe_error_payload,
   ecto_repos: [],
   field_constructor: AbsintheErrorPayload.FieldConstructor
-
-# This configuration is loaded before any dependency and is restricted
-# to this project. If another project depends on this project, this
-# file won't be loaded nor affect the parent project. For this reason,
-# if you want to provide default values for your application for
-# 3rd-party users, it should be done in your "mix.exs" file.
-
-# You can configure for your application as:
-#
-#     config :absinthe_error_payload, key: :value
-#
-# And access this configuration in your application as:
-#
-#     Application.get_env(:absinthe_error_payload, :key)
-#
-# Or configure a 3rd-party app:
-#
-#     config :logger, level: :info
-#
-
-# It is also possible to import configuration files, relative to this
-# directory. For example, you can emulate configuration per environment
-# by uncommenting the line below and defining dev.exs, test.exs and such.
-# Configuration from the imported file will override the ones defined
-# here (which is why it is important to import them last).
-#
-#     import_config "#{Mix.env}.exs"
diff --git a/test/changeset_parser_custom_field_constructor_test.exs b/test/changeset_parser_custom_field_constructor_test.exs
index 08e67ae..5feed73 100644
--- a/test/changeset_parser_custom_field_constructor_test.exs
+++ b/test/changeset_parser_custom_field_constructor_test.exs
@@ -62,7 +62,12 @@ defmodule AbsintheErrorPayload.ChangesetParserCustomFieldConstructorTest do
   end
 
   setup do
+    original_field_constructor = Application.get_env(:absinthe_error_payload, :field_constructor)
     Application.put_env(:absinthe_error_payload, :field_constructor, CustomFieldConstructor)
+
+    on_exit(fn ->
+      Application.put_env(:absinthe_error_payload, :field_constructor, original_field_constructor)
+    end)
   end
 
   describe "construct_message/2" do