diff --git a/composer.json b/composer.json
index b18f188..41db2e8 100644
--- a/composer.json
+++ b/composer.json
@@ -26,6 +26,7 @@
     "require": {
         "php": "^8.3",
         "composer-plugin-api": "^2.0",
+        "brianium/paratest": "^7.17",
         "composer/composer": "^2.9",
         "dg/bypass-finals": "^1.9",
         "ergebnis/composer-normalize": "^2.50",
diff --git a/src/Command/TestsCommand.php b/src/Command/TestsCommand.php
index fc1706c..36e5711 100644
--- a/src/Command/TestsCommand.php
+++ b/src/Command/TestsCommand.php
@@ -103,6 +103,12 @@ protected function configure(): void
                 mode: InputOption::VALUE_OPTIONAL,
                 description: 'Filter which tests to run based on a pattern.',
             )
+            ->addOption(
+                name: 'parallel',
+                shortcut: 'p',
+                mode: InputOption::VALUE_OPTIONAL,
+                description: 'Run tests in parallel using ParaTest. Optional number of workers.',
+            )
             ->addOption(
                 name: 'min-coverage',
                 mode: InputOption::VALUE_REQUIRED,
@@ -123,8 +129,6 @@ protected function configure(): void
      */
     protected function execute(InputInterface $input, OutputInterface $output): int
     {
-        $output->writeln('<info>Running PHPUnit tests...</info>');
-
         try {
             $minimumCoverage = $this->resolveMinimumCoverage($input);
         } catch (InvalidArgumentException $invalidArgumentException) {
@@ -134,13 +138,8 @@ protected function execute(InputInterface $input, OutputInterface $output): int
         }
 
         $arguments = [
-            $this->getAbsolutePath('vendor/bin/phpunit'),
             '--configuration=' . parent::getConfigFile(self::CONFIG),
             '--bootstrap=' . $this->resolvePath($input, 'bootstrap'),
-            '--display-deprecations',
-            '--display-phpunit-deprecations',
-            '--display-incomplete',
-            '--display-skipped',
         ];
 
         if (! $input->getOption('no-cache')) {
@@ -149,11 +148,26 @@ protected function execute(InputInterface $input, OutputInterface $output): int
 
         $coverageReportPath = $this->configureCoverageArguments($input, $arguments, null !== $minimumCoverage);
 
-        if ($input->getOption('filter')) {
+        if (null !== $input->getOption('filter')) {
             $arguments[] = '--filter=' . $input->getOption('filter');
         }
 
-        $command = new Process([...$arguments, $input->getArgument('path')]);
+        $parallel = null !== $input->getOption('parallel');
+
+        $command = $this->getAbsolutePath(\sprintf('vendor/bin/%s', $parallel ? 'paratest' : 'phpunit'));
+
+        if (! $parallel) {
+            $arguments[] = '--display-deprecations';
+            $arguments[] = '--display-phpunit-deprecations';
+            $arguments[] = '--display-incomplete';
+            $arguments[] = '--display-skipped';
+        } else {
+            $arguments[] = '--processes=' . ($input->getOption('parallel') ?: 'auto');
+        }
+
+        $output->writeln('<info>Running tests using ' . ($parallel ? 'ParaTest' : 'PHPUnit') . '...</info>');
+
+        $command = new Process([$command, ...$arguments, $input->getArgument('path')]);
 
         $result = parent::runProcess($command, $output);
 
diff --git a/tests/GitAttributes/CandidateProviderTest.php b/tests/GitAttributes/CandidateProviderTest.php
index 84f840a..ec63f61 100644
--- a/tests/GitAttributes/CandidateProviderTest.php
+++ b/tests/GitAttributes/CandidateProviderTest.php
@@ -26,7 +26,7 @@
 #[CoversClass(CandidateProvider::class)]
 final class CandidateProviderTest extends TestCase
 {
-    private readonly CandidateProvider $provider;
+    private CandidateProvider $provider;
 
     /**
      * @return void
diff --git a/tests/GitAttributes/ExistenceCheckerTest.php b/tests/GitAttributes/ExistenceCheckerTest.php
index f07bb68..eeb1621 100644
--- a/tests/GitAttributes/ExistenceCheckerTest.php
+++ b/tests/GitAttributes/ExistenceCheckerTest.php
@@ -34,9 +34,9 @@ final class ExistenceCheckerTest extends TestCase
     /**
      * @property ObjectProphecy<Filesystem> $filesystem
      */
-    private readonly ObjectProphecy $filesystem;
+    private ObjectProphecy $filesystem;
 
-    private readonly ExistenceChecker $checker;
+    private ExistenceChecker $checker;
 
     /**
      * @return void
diff --git a/tests/GitIgnore/ReaderTest.php b/tests/GitIgnore/ReaderTest.php
index f61d669..8ddd42a 100644
--- a/tests/GitIgnore/ReaderTest.php
+++ b/tests/GitIgnore/ReaderTest.php
@@ -33,7 +33,7 @@
 #[UsesClass(GitIgnore::class)]
 final class ReaderTest extends TestCase
 {
-    private readonly Reader $reader;
+    private Reader $reader;
 
     /**
      * @return void