diff --git a/composer.json b/composer.json
index 3b33405..300c87d 100644
--- a/composer.json
+++ b/composer.json
@@ -37,9 +37,9 @@
         }
     },
     "autoload-dev": {
-        "classmap": [
-            "./tests/"
-        ]
+        "psr-4": {
+            "PHP_Parallel_Lint\\PhpParallelLint\\Tests\\": "tests/"
+        }
     },
     "bin": [
         "parallel-lint"
diff --git a/phpcs.xml.dist b/phpcs.xml.dist
index 99644bf..dba4930 100644
--- a/phpcs.xml.dist
+++ b/phpcs.xml.dist
@@ -85,13 +85,13 @@
 
     <!-- To be addressed in test refactor. -->
     <rule ref="PSR1.Classes.ClassDeclaration.MultipleClasses">
-        <exclude-pattern>/tests/Output\.phpt$</exclude-pattern>
-    </rule>
-    <rule ref="PSR1.Classes.ClassDeclaration.MissingNamespace">
-        <exclude-pattern>/tests/*\.php[t]?$</exclude-pattern>
+        <exclude-pattern>/tests/OutputTest\.php$</exclude-pattern>
     </rule>
     <rule ref="PSR1.Files.SideEffects.FoundWithSymbols">
-        <exclude-pattern>/tests/*\.phpt$</exclude-pattern>
+        <exclude-pattern>/tests/*\.php$</exclude-pattern>
+    </rule>
+    <rule ref="PSR1.Classes.ClassDeclaration.MissingNamespace">
+        <exclude-pattern>/tests/skip-on-5\.3/*\.php$</exclude-pattern>
     </rule>
     <rule ref="PSR12.Files.FileHeader.SpacingAfterBlock">
         <exclude-pattern>/tests/skip-on-5.3/trait\.php$</exclude-pattern>
diff --git a/tests/Manager.run.phpt b/tests/ManagerRunTest.php
similarity index 98%
rename from tests/Manager.run.phpt
rename to tests/ManagerRunTest.php
index 982881f..55194f0 100644
--- a/tests/Manager.run.phpt
+++ b/tests/ManagerRunTest.php
@@ -4,6 +4,8 @@
  * @testCase
  */
 
+namespace PHP_Parallel_Lint\PhpParallelLint\Tests;
+
 require_once __DIR__ . '/../src/polyfill.php';
 require __DIR__ . '/../vendor/autoload.php';
 
diff --git a/tests/Output.phpt b/tests/OutputTest.php
similarity index 98%
rename from tests/Output.phpt
rename to tests/OutputTest.php
index f3453d2..ea11686 100644
--- a/tests/Output.phpt
+++ b/tests/OutputTest.php
@@ -4,6 +4,8 @@
  * @testCase
  */
 
+namespace PHP_Parallel_Lint\PhpParallelLint\Tests;
+
 require_once __DIR__ . '/../src/polyfill.php';
 require __DIR__ . '/../vendor/autoload.php';
 
diff --git a/tests/ParallelLint.lint.phpt b/tests/ParallelLintLintTest.php
similarity index 99%
rename from tests/ParallelLint.lint.phpt
rename to tests/ParallelLintLintTest.php
index 30b28ac..0d2e478 100644
--- a/tests/ParallelLint.lint.phpt
+++ b/tests/ParallelLintLintTest.php
@@ -4,6 +4,8 @@
  * @testCase
  */
 
+namespace PHP_Parallel_Lint\PhpParallelLint\Tests;
+
 require_once __DIR__ . '/../src/polyfill.php';
 require __DIR__ . '/../vendor/autoload.php';
 
diff --git a/tests/Settings.parseArguments.phpt b/tests/SettingsParseArgumentsTest.php
similarity index 99%
rename from tests/Settings.parseArguments.phpt
rename to tests/SettingsParseArgumentsTest.php
index 46fe83a..48cbadc 100644
--- a/tests/Settings.parseArguments.phpt
+++ b/tests/SettingsParseArgumentsTest.php
@@ -4,6 +4,8 @@
  * @testCase
  */
 
+namespace PHP_Parallel_Lint\PhpParallelLint\Tests;
+
 require_once __DIR__ . '/../src/polyfill.php';
 require __DIR__ . '/../vendor/autoload.php';
 
diff --git a/tests/SkipLintProcess.phpt b/tests/SkipLintProcessTest.php
similarity index 95%
rename from tests/SkipLintProcess.phpt
rename to tests/SkipLintProcessTest.php
index ada9125..88fd086 100644
--- a/tests/SkipLintProcess.phpt
+++ b/tests/SkipLintProcessTest.php
@@ -4,6 +4,8 @@
  * @testCase
  */
 
+namespace PHP_Parallel_Lint\PhpParallelLint\Tests;
+
 require_once __DIR__ . '/../src/polyfill.php';
 require __DIR__ . '/../vendor/autoload.php';
 
diff --git a/tests/SyntaxError.normalizeMessage.phpt b/tests/SyntaxErrorNormalizeMessageTest.php
similarity index 95%
rename from tests/SyntaxError.normalizeMessage.phpt
rename to tests/SyntaxErrorNormalizeMessageTest.php
index e3558ea..69249b4 100644
--- a/tests/SyntaxError.normalizeMessage.phpt
+++ b/tests/SyntaxErrorNormalizeMessageTest.php
@@ -4,6 +4,8 @@
  * @testCase
  */
 
+namespace PHP_Parallel_Lint\PhpParallelLint\Tests;
+
 require_once __DIR__ . '/../src/polyfill.php';
 require __DIR__ . '/../vendor/autoload.php';