diff --git a/.github/workflows/php-workshop.yml b/.github/workflows/php-workshop.yml
index 37040d83..7568a445 100644
--- a/.github/workflows/php-workshop.yml
+++ b/.github/workflows/php-workshop.yml
@@ -24,6 +24,7 @@ jobs:
         with:
           php-version: ${{ matrix.php }}
           tools: composer:v2
+          ini-values: opcache.enable=0
 
       - name: Install Dependencies
         run: composer update --prefer-dist
diff --git a/app/config.php b/app/config.php
index 7b64b923..d67ab76a 100644
--- a/app/config.php
+++ b/app/config.php
@@ -384,28 +384,19 @@ function (CgiResult $result) use ($c) {
             ],
         ],
         'code-patcher' => [
-            'cli.verify.start' => [
-                containerListener(CodePatchListener::class, 'patch'),
-            ],
-            'cli.verify.finish' => [
+            'application.tear-down' => [
                 containerListener(CodePatchListener::class, 'revert'),
             ],
-            'cli.run.start' => [
+            'verify.pre.execute' => [
                 containerListener(CodePatchListener::class, 'patch'),
             ],
-            'cli.run.finish' => [
+            'verify.post.execute' => [
                 containerListener(CodePatchListener::class, 'revert'),
             ],
-            'cgi.verify.start' => [
-                containerListener(CodePatchListener::class, 'patch'),
-            ],
-            'cgi.verify.finish' => [
-                containerListener(CodePatchListener::class, 'revert'),
-            ],
-            'cgi.run.start' => [
+            'run.start' => [
                 containerListener(CodePatchListener::class, 'patch'),
             ],
-            'cgi.run.finish' => [
+            'run.finish' => [
                 containerListener(CodePatchListener::class, 'revert'),
             ],
         ],
diff --git a/src/Application.php b/src/Application.php
index 3aec2936..2a4cff7c 100644
--- a/src/Application.php
+++ b/src/Application.php
@@ -7,11 +7,14 @@
 use DI\Container;
 use DI\ContainerBuilder;
 use PhpSchool\PhpWorkshop\Check\CheckRepository;
+use PhpSchool\PhpWorkshop\Event\Event;
+use PhpSchool\PhpWorkshop\Event\EventDispatcher;
 use PhpSchool\PhpWorkshop\Exception\InvalidArgumentException;
 use PhpSchool\PhpWorkshop\Exception\MissingArgumentException;
 use PhpSchool\PhpWorkshop\Factory\ResultRendererFactory;
 use PhpSchool\PhpWorkshop\Output\OutputInterface;
 use Psr\Container\ContainerInterface;
+use Psr\Log\LoggerInterface;
 use RuntimeException;
 
 use function class_exists;
@@ -192,6 +195,12 @@ public function configure(): ContainerInterface
             }
         }
 
+        set_error_handler(function () use ($container): bool {
+            $this->tearDown($container);
+
+            return false; // Use default error handler
+        });
+
         return $container;
     }
 
@@ -227,6 +236,8 @@ public function run(): int
                 $message = str_replace($basePath, '', $message);
             }
 
+            $this->tearDown($container);
+
             $container
                 ->get(OutputInterface::class)
                 ->printError(
@@ -268,4 +279,15 @@ private function getContainer(): Container
 
         return $containerBuilder->build();
     }
+
+    private function tearDown(ContainerInterface $container): void
+    {
+        try {
+            $container
+                ->get(EventDispatcher::class)
+                ->dispatch(new Event('application.tear-down'));
+        } catch (\Throwable $t) {
+            $container->get(LoggerInterface::class)->error($t->getMessage(), ['exception' => $t]);
+        }
+    }
 }
diff --git a/src/Exercise/AbstractExercise.php b/src/Exercise/AbstractExercise.php
index b94d204d..1a5355e6 100644
--- a/src/Exercise/AbstractExercise.php
+++ b/src/Exercise/AbstractExercise.php
@@ -15,6 +15,10 @@
  */
 abstract class AbstractExercise
 {
+    /**
+     * @var SolutionInterface|null
+     */
+    protected $solution;
 
     /**
      * Get the name of the exercise, like `Hello World!`.
@@ -35,15 +39,19 @@ abstract public function getName(): string;
      */
     public function getSolution(): SolutionInterface
     {
-        return SingleFileSolution::fromFile(
-            (string) realpath(
-                sprintf(
-                    '%s/../../exercises/%s/solution/solution.php',
-                    dirname((string) (new ReflectionClass(static::class))->getFileName()),
-                    self::normaliseName($this->getName())
+        if (null === $this->solution) {
+            $this->solution = SingleFileSolution::fromFile(
+                (string)realpath(
+                    sprintf(
+                        '%s/../../exercises/%s/solution/solution.php',
+                        dirname((string)(new ReflectionClass(static::class))->getFileName()),
+                        self::normaliseName($this->getName())
+                    )
                 )
-            )
-        );
+            );
+        }
+
+        return $this->solution;
     }
 
     /**
diff --git a/src/Listener/CodePatchListener.php b/src/Listener/CodePatchListener.php
index a1266167..53ed0845 100644
--- a/src/Listener/CodePatchListener.php
+++ b/src/Listener/CodePatchListener.php
@@ -6,10 +6,12 @@
 
 use PhpSchool\PhpWorkshop\CodePatcher;
 use PhpSchool\PhpWorkshop\Event\ExerciseRunnerEvent;
+use PhpSchool\PhpWorkshop\Exercise\ProvidesSolution;
+use PhpSchool\PhpWorkshop\Solution\SolutionFile;
 use RuntimeException;
 
 /**
- * Listener which patches student's solutions
+ * Listener which patches internal and student's solutions
  */
 class CodePatchListener
 {
@@ -19,9 +21,9 @@ class CodePatchListener
     private $codePatcher;
 
     /**
-     * @var string
+     * @var array<string, string>
      */
-    private $originalCode;
+    private $originalCode = [];
 
     /**
      * @param CodePatcher $codePatcher
@@ -36,34 +38,36 @@ public function __construct(CodePatcher $codePatcher)
      */
     public function patch(ExerciseRunnerEvent $event): void
     {
-        $fileName = $event->getInput()->getArgument('program');
+        $files = [
+            $event->getInput()->getArgument('program'),
+        ];
 
-        if (null === $fileName) {
-            return;
+        $exercise = $event->getExercise();
+        if ($exercise instanceof ProvidesSolution) {
+            $files[] = $exercise->getSolution()->getEntryPoint();
         }
 
-        $this->originalCode = (string) file_get_contents($fileName);
-        file_put_contents(
-            $fileName,
-            $this->codePatcher->patch($event->getExercise(), $this->originalCode)
-        );
+        foreach (array_filter($files) as $fileName) {
+            $this->originalCode[$fileName] = (string) file_get_contents($fileName);
+
+            file_put_contents(
+                $fileName,
+                $this->codePatcher->patch($event->getExercise(), $this->originalCode[$fileName])
+            );
+        }
     }
 
     /**
-     * @param ExerciseRunnerEvent $event
+     * @param \PhpSchool\PhpWorkshop\Event\EventInterface $event
      */
-    public function revert(ExerciseRunnerEvent $event): void
+    public function revert(\PhpSchool\PhpWorkshop\Event\EventInterface $event): void
     {
-        if (null === $this->originalCode) {
-            throw new RuntimeException('Can only revert previously patched code');
-        }
-
-        $fileName = $event->getInput()->getArgument('program');
-
-        if (null === $fileName) {
+        if (null === $this->originalCode || empty($this->originalCode)) {
             return;
         }
 
-        file_put_contents($fileName, $this->originalCode);
+        foreach ($this->originalCode as $fileName => $contents) {
+            file_put_contents($fileName, $contents);
+        }
     }
 }
diff --git a/src/Solution/DirectorySolution.php b/src/Solution/DirectorySolution.php
index b67b55fe..0c2242f2 100644
--- a/src/Solution/DirectorySolution.php
+++ b/src/Solution/DirectorySolution.php
@@ -40,7 +40,7 @@ class DirectorySolution implements SolutionInterface
      * @param array<string> $exclusions An array of file names to exclude from the folder.
      * @throws InvalidArgumentException If the entry point does not exist in the folder.
      */
-    public function __construct(string $directory, string $entryPoint, array $exclusions = [])
+    private function __construct(string $directory, string $entryPoint, array $exclusions = [])
     {
         $directory  = (string) realpath(rtrim($directory, '/'));
         $entryPoint = ltrim($entryPoint, '/');
@@ -81,15 +81,20 @@ public function __construct(string $directory, string $entryPoint, array $exclus
      * @param string $directory The directory to search for files.
      * @param array<string> $exclusions An array of file names to exclude from the folder.
      * @param string $entryPoint The relative path from the directory of the entry point file.
-     * @return self
+     * @return SolutionInterface
      */
-    public static function fromDirectory(string $directory, array $exclusions = [], $entryPoint = 'solution.php'): self
-    {
-        return new self($directory, $entryPoint, array_merge($exclusions, ['composer.lock', 'vendor']));
+    public static function fromDirectory(
+        string $directory,
+        array $exclusions = [],
+        $entryPoint = 'solution.php'
+    ): SolutionInterface {
+        return InTempSolution::fromSolution(
+            new self($directory, $entryPoint, array_merge($exclusions, ['composer.lock', 'vendor']))
+        );
     }
 
     /**
-     * Get the entry point. This is the PHP file that PHO would execute in order to run the
+     * Get the entry point. This is the PHP file that PHP would execute in order to run the
      * program. This should be the absolute path.
      *
      * @return string
diff --git a/src/Solution/InTempSolution.php b/src/Solution/InTempSolution.php
new file mode 100644
index 00000000..1bbc4667
--- /dev/null
+++ b/src/Solution/InTempSolution.php
@@ -0,0 +1,119 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpSchool\PhpWorkshop\Solution;
+
+use PhpSchool\PhpWorkshop\Utils\System;
+use Symfony\Component\Filesystem\Filesystem;
+
+class InTempSolution implements SolutionInterface
+{
+    /**
+     * @var string
+     */
+    private $baseDirectory;
+
+    /**
+     * @var string
+     */
+    private $entryPoint;
+
+    /**
+     * @var SolutionFile[]
+     */
+    private $files;
+
+    private function __construct(SolutionInterface $solution)
+    {
+        $fileSystem = new Filesystem();
+
+        $tempDir = System::tempDir();
+        $currentPath = explode('/', System::realpath(__DIR__));
+        $solutionPath = explode('/', System::realpath($solution->getBaseDirectory()));
+        $entryPointPath = explode('/', System::realpath($solution->getEntryPoint()));
+
+        $intersection = array_intersect($currentPath, $solutionPath);
+
+        if (count($intersection) <= 1) {
+            $intersection = explode('/', $tempDir);
+        }
+
+        $basename = implode('/', array_diff($solutionPath, $intersection));
+        $entrypoint = implode('/', array_diff($entryPointPath, $intersection));
+
+        $this->baseDirectory = sprintf('%s/php-school/%s', $tempDir, $basename);
+        $this->entryPoint = sprintf('%s/php-school/%s', $tempDir, $entrypoint);
+
+        if ($fileSystem->exists($this->baseDirectory)) {
+            $fileSystem->remove($this->baseDirectory);
+        }
+
+        $fileSystem->mkdir($this->baseDirectory);
+
+        $dirIterator = new \RecursiveDirectoryIterator(
+            $solution->getBaseDirectory(),
+            \RecursiveDirectoryIterator::SKIP_DOTS
+        );
+        $iterator = new \RecursiveIteratorIterator($dirIterator, \RecursiveIteratorIterator::SELF_FIRST);
+
+        foreach ($iterator as $file) {
+            $target = sprintf('%s/%s', $this->baseDirectory, $iterator->getSubPathName());
+            $file->isDir()
+                ? $fileSystem->mkdir($target)
+                : $fileSystem->copy($file->getPathname(), $target);
+        }
+
+        $this->files = array_map(function (SolutionFile $solutionFile) use ($intersection, $tempDir) {
+            $filePath = explode('/', System::realpath($solutionFile->__toString()));
+            $file = implode('/', array_diff($filePath, $intersection));
+            return SolutionFile::fromFile(sprintf('%s/php-school/%s', $tempDir, $file));
+        }, $solution->getFiles());
+    }
+
+    public static function fromSolution(SolutionInterface $solution): SolutionInterface
+    {
+        return new self($solution);
+    }
+
+    /**
+     * Get the entry point. This is the PHP file that PHP would execute in order to run the
+     * program. This should be the absolute path.
+     *
+     * @return string
+     */
+    public function getEntryPoint(): string
+    {
+        return $this->entryPoint;
+    }
+
+    /**
+     * Get all the files which are contained with the solution.
+     *
+     * @return array<SolutionFile>
+     */
+    public function getFiles(): array
+    {
+        return $this->files;
+    }
+
+    /**
+     * Get the absolute path to the directory containing the solution.
+     *
+     * @return string
+     */
+    public function getBaseDirectory(): string
+    {
+        return $this->baseDirectory;
+    }
+
+    /**
+     * Check whether there is a `composer.lock` file in the base directory.
+     *
+     * @return bool
+     */
+    public function hasComposerFile(): bool
+    {
+        return file_exists(sprintf('%s/composer.lock', $this->baseDirectory));
+    }
+}
diff --git a/src/Solution/SingleFileSolution.php b/src/Solution/SingleFileSolution.php
index b32aac67..1804d89a 100644
--- a/src/Solution/SingleFileSolution.php
+++ b/src/Solution/SingleFileSolution.php
@@ -20,7 +20,7 @@ class SingleFileSolution implements SolutionInterface
      * @param string $file The absolute path of the reference solution.
      * @throws InvalidArgumentException If the file does not exist.
      */
-    public function __construct(string $file)
+    private function __construct(string $file)
     {
         if (!file_exists($file)) {
             throw new InvalidArgumentException(sprintf('File: "%s" does not exist', $file));
@@ -33,12 +33,12 @@ public function __construct(string $file)
      * Static constructor to build an instance from an absolute file path.
      *
      * @param string $file The absolute path of the reference solution.
-     * @return self
+     * @return SolutionInterface
      * @throws InvalidArgumentException If the file does not exist.
      */
-    public static function fromFile(string $file): self
+    public static function fromFile(string $file): SolutionInterface
     {
-        return new self($file);
+        return InTempSolution::fromSolution(new self($file));
     }
 
     /**
diff --git a/src/TestUtils/SolutionPathTransformer.php b/src/TestUtils/SolutionPathTransformer.php
new file mode 100644
index 00000000..5000f582
--- /dev/null
+++ b/src/TestUtils/SolutionPathTransformer.php
@@ -0,0 +1,21 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpSchool\PhpWorkshop\TestUtils;
+
+class SolutionPathTransformer
+{
+    public static function tempPathToSolutionTempPath(string $tmpFilePath): string
+    {
+        $tmpDir = realpath(sys_get_temp_dir());
+
+        if (!$tmpDir) {
+            throw new \RuntimeException();
+        }
+
+        $file = str_replace($tmpDir, '', $tmpFilePath);
+
+        return sprintf('%s/php-school/%s', $tmpDir, ltrim($file, '/'));
+    }
+}
diff --git a/src/Utils/System.php b/src/Utils/System.php
new file mode 100644
index 00000000..6d2c2f7d
--- /dev/null
+++ b/src/Utils/System.php
@@ -0,0 +1,24 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpSchool\PhpWorkshop\Utils;
+
+class System
+{
+    public static function realpath(string $path): string
+    {
+        $realpath = realpath($path);
+
+        if (false === $realpath) {
+            throw new \RuntimeException(sprintf('Failed to get realpath of "%s"', $path));
+        }
+
+        return $realpath;
+    }
+
+    public static function tempDir(): string
+    {
+        return self::realpath(sys_get_temp_dir());
+    }
+}
diff --git a/test/Exercise/AbstractExerciseTest.php b/test/Exercise/AbstractExerciseTest.php
index cddc98b1..676718ac 100644
--- a/test/Exercise/AbstractExerciseTest.php
+++ b/test/Exercise/AbstractExerciseTest.php
@@ -24,14 +24,14 @@ public function testGetSolution(string $name): void
     {
         $exercise   = new AbstractExerciseImpl($name);
         $path       = __DIR__ . '/../../exercises/array-we-go/solution/solution.php';
-        mkdir(dirname($path), 0777, true);
-        touch($path);
+        @mkdir(dirname($path), 0777, true);
+        file_put_contents($path, 'FILE CONTENTS');
         $solution = $exercise->getSolution();
         $this->assertInstanceOf(SolutionInterface::class, $solution);
         $files = $solution->getFiles();
         $this->assertCount(1, $files);
         $this->assertInstanceOf(SolutionFile::class, $files[0]);
-        $this->assertSame(realpath($path), $files[0]->__toString());
+        $this->assertSame('FILE CONTENTS', file_get_contents($files[0]->__toString()));
         unlink($path);
         rmdir(__DIR__ . '/../../exercises/array-we-go/solution');
         rmdir(__DIR__ . '/../../exercises/array-we-go');
diff --git a/test/Listener/CodePatchListenerTest.php b/test/Listener/CodePatchListenerTest.php
index d686f41c..6474df1e 100644
--- a/test/Listener/CodePatchListenerTest.php
+++ b/test/Listener/CodePatchListenerTest.php
@@ -38,19 +38,6 @@ public function setUp(): void
         touch($this->file);
     }
 
-    public function testRevertThrowsExceptionIfPatchNotPreviouslyCalled(): void
-    {
-        $input    = new Input('app', ['program' => $this->file]);
-        $exercise = $this->createMock(ExerciseInterface::class);
-
-        $listener   = new CodePatchListener($this->codePatcher);
-        $event      = new ExerciseRunnerEvent('event', $exercise, $input);
-
-        $this->expectException(RuntimeException::class);
-        $this->expectExceptionMessage('Can only revert previously patched code');
-        $listener->revert($event);
-    }
-
     public function testPatchUpdatesCode(): void
     {
         file_put_contents($this->file, 'ORIGINAL CONTENT');
diff --git a/test/ResultRenderer/ResultsRendererTest.php b/test/ResultRenderer/ResultsRendererTest.php
index f853fbaf..9bded6dc 100644
--- a/test/ResultRenderer/ResultsRendererTest.php
+++ b/test/ResultRenderer/ResultsRendererTest.php
@@ -119,11 +119,11 @@ public function testRenderSuccessWithSolution(): void
         $exerciseRepo->method('count')->willReturn(2);
 
         $tmpFile = sprintf('%s/%s/some-file', sys_get_temp_dir(), $this->getName());
-        mkdir(dirname($tmpFile));
+        @mkdir(dirname($tmpFile));
         file_put_contents($tmpFile, 'FILE CONTENTS');
 
         $exercise = new CliExerciseImpl();
-        $exercise->setSolution(new SingleFileSolution($tmpFile));
+        $exercise->setSolution(SingleFileSolution::fromFile($tmpFile));
 
         $renderer = new ResultsRenderer(
             'app',
@@ -165,11 +165,11 @@ public function testRenderSuccessWithPhpSolutionFileIsSyntaxHighlighted(): void
         $exerciseRepo->method('count')->willReturn(2);
 
         $tmpFile = sprintf('%s/%s/some-file.php', sys_get_temp_dir(), $this->getName());
-        mkdir(dirname($tmpFile));
+        @mkdir(dirname($tmpFile));
         file_put_contents($tmpFile, 'FILE CONTENTS');
 
         $exercise = new CliExerciseImpl();
-        $exercise->setSolution(new SingleFileSolution($tmpFile));
+        $exercise->setSolution(SingleFileSolution::fromFile($tmpFile));
 
         $syntaxHighlighter = $this->createMock(KeyLighter::class);
         $php = new Php();
diff --git a/test/Solution/DirectorySolutionTest.php b/test/Solution/DirectorySolutionTest.php
index 37b18356..1e5f4b9a 100644
--- a/test/Solution/DirectorySolutionTest.php
+++ b/test/Solution/DirectorySolutionTest.php
@@ -4,6 +4,7 @@
 
 use InvalidArgumentException;
 use PhpSchool\PhpWorkshop\Solution\DirectorySolution;
+use PhpSchool\PhpWorkshop\TestUtils\SolutionPathTransformer;
 use PHPUnit\Framework\TestCase;
 
 class DirectorySolutionTest extends TestCase
@@ -32,18 +33,23 @@ public function testWithDefaultEntryPoint(): void
 
         $solution = DirectorySolution::fromDirectory($tempPath);
 
-        $this->assertSame($tempPath, $solution->getBaseDirectory());
+        $expectedBaseDir = SolutionPathTransformer::tempPathToSolutionTempPath($tempPath);
+
+        $this->assertSame($expectedBaseDir, $solution->getBaseDirectory());
         $this->assertFalse($solution->hasComposerFile());
-        $this->assertSame(sprintf('%s/solution.php', $tempPath), $solution->getEntryPoint());
+        $this->assertSame(sprintf('%s/solution.php', $expectedBaseDir), $solution->getEntryPoint());
         $files = $solution->getFiles();
         $this->assertCount(2, $files);
 
-        $this->assertSame(sprintf('%s/solution.php', $tempPath), $files[0]->__toString());
-        $this->assertSame(sprintf('%s/some-class.php', $tempPath), $files[1]->__toString());
+        $this->assertSame(sprintf('%s/solution.php', $expectedBaseDir), $files[0]->__toString());
+        $this->assertSame(sprintf('%s/some-class.php', $expectedBaseDir), $files[1]->__toString());
 
+        unlink(sprintf('%s/solution.php', $expectedBaseDir));
+        unlink(sprintf('%s/some-class.php', $expectedBaseDir));
         unlink(sprintf('%s/solution.php', $tempPath));
         unlink(sprintf('%s/some-class.php', $tempPath));
         rmdir($tempPath);
+        rmdir($expectedBaseDir);
     }
 
     public function testWithManualEntryPoint(): void
@@ -55,18 +61,23 @@ public function testWithManualEntryPoint(): void
 
         $solution = DirectorySolution::fromDirectory($tempPath, [], 'index.php');
 
-        $this->assertSame($tempPath, $solution->getBaseDirectory());
+        $expectedBaseDir = SolutionPathTransformer::tempPathToSolutionTempPath($tempPath);
+
+        $this->assertSame($expectedBaseDir, $solution->getBaseDirectory());
         $this->assertFalse($solution->hasComposerFile());
-        $this->assertSame(sprintf('%s/index.php', $tempPath), $solution->getEntryPoint());
+        $this->assertSame(sprintf('%s/index.php', $expectedBaseDir), $solution->getEntryPoint());
         $files = $solution->getFiles();
         $this->assertCount(2, $files);
 
-        $this->assertSame(sprintf('%s/index.php', $tempPath), $files[0]->__toString());
-        $this->assertSame(sprintf('%s/some-class.php', $tempPath), $files[1]->__toString());
+        $this->assertSame(sprintf('%s/index.php', $expectedBaseDir), $files[0]->__toString());
+        $this->assertSame(sprintf('%s/some-class.php', $expectedBaseDir), $files[1]->__toString());
 
+        unlink(sprintf('%s/index.php', $expectedBaseDir));
+        unlink(sprintf('%s/some-class.php', $expectedBaseDir));
         unlink(sprintf('%s/index.php', $tempPath));
         unlink(sprintf('%s/some-class.php', $tempPath));
         rmdir($tempPath);
+        rmdir($expectedBaseDir);
     }
 
     public function testHasComposerFileReturnsTrueIfPresent(): void
@@ -79,15 +90,20 @@ public function testHasComposerFileReturnsTrueIfPresent(): void
 
         $solution = DirectorySolution::fromDirectory($tempPath);
 
-        $this->assertSame($tempPath, $solution->getBaseDirectory());
+        $expectedBaseDir = SolutionPathTransformer::tempPathToSolutionTempPath($tempPath);
+
+        $this->assertSame($expectedBaseDir, $solution->getBaseDirectory());
         $this->assertTrue($solution->hasComposerFile());
-        $this->assertSame(sprintf('%s/solution.php', $tempPath), $solution->getEntryPoint());
+        $this->assertSame(sprintf('%s/solution.php', $expectedBaseDir), $solution->getEntryPoint());
         $files = $solution->getFiles();
         $this->assertCount(2, $files);
 
-        $this->assertSame(sprintf('%s/solution.php', $tempPath), $files[0]->__toString());
-        $this->assertSame(sprintf('%s/some-class.php', $tempPath), $files[1]->__toString());
+        $this->assertSame(sprintf('%s/solution.php', $expectedBaseDir), $files[0]->__toString());
+        $this->assertSame(sprintf('%s/some-class.php', $expectedBaseDir), $files[1]->__toString());
 
+        unlink(sprintf('%s/composer.lock', $expectedBaseDir));
+        unlink(sprintf('%s/solution.php', $expectedBaseDir));
+        unlink(sprintf('%s/some-class.php', $expectedBaseDir));
         unlink(sprintf('%s/composer.lock', $tempPath));
         unlink(sprintf('%s/solution.php', $tempPath));
         unlink(sprintf('%s/some-class.php', $tempPath));
@@ -105,17 +121,23 @@ public function testWithExceptions(): void
 
         $solution = DirectorySolution::fromDirectory($tempPath, $exclusions);
 
-        $this->assertSame(sprintf('%s/solution.php', $tempPath), $solution->getEntryPoint());
+        $expectedBaseDir = SolutionPathTransformer::tempPathToSolutionTempPath($tempPath);
+
+        $this->assertSame(sprintf('%s/solution.php', $expectedBaseDir), $solution->getEntryPoint());
         $files = $solution->getFiles();
         $this->assertCount(2, $files);
 
-        $this->assertSame(sprintf('%s/solution.php', $tempPath), $files[0]->__toString());
-        $this->assertSame(sprintf('%s/some-class.php', $tempPath), $files[1]->__toString());
+        $this->assertSame(sprintf('%s/solution.php', $expectedBaseDir), $files[0]->__toString());
+        $this->assertSame(sprintf('%s/some-class.php', $expectedBaseDir), $files[1]->__toString());
 
+        unlink(sprintf('%s/solution.php', $expectedBaseDir));
+        unlink(sprintf('%s/some-class.php', $expectedBaseDir));
+        unlink(sprintf('%s/exclude.txt', $expectedBaseDir));
         unlink(sprintf('%s/solution.php', $tempPath));
         unlink(sprintf('%s/some-class.php', $tempPath));
         unlink(sprintf('%s/exclude.txt', $tempPath));
         rmdir($tempPath);
+        rmdir($expectedBaseDir);
     }
 
     public function testWithNestedDirectories(): void
@@ -134,15 +156,17 @@ public function testWithNestedDirectories(): void
 
         $solution = DirectorySolution::fromDirectory($tempPath);
 
-        $this->assertSame(sprintf('%s/solution.php', $tempPath), $solution->getEntryPoint());
+        $expectedBaseDir = SolutionPathTransformer::tempPathToSolutionTempPath($tempPath);
+
+        $this->assertSame(sprintf('%s/solution.php', $expectedBaseDir), $solution->getEntryPoint());
         $files = $solution->getFiles();
         $this->assertCount(5, $files);
 
-        $this->assertSame(sprintf('%s/composer.json', $tempPath), $files[0]->__toString());
-        $this->assertSame(sprintf('%s/nested/another-class.php', $tempPath), $files[1]->__toString());
-        $this->assertSame(sprintf('%s/nested/deep/even-more.php', $tempPath), $files[2]->__toString());
-        $this->assertSame(sprintf('%s/solution.php', $tempPath), $files[3]->__toString());
-        $this->assertSame(sprintf('%s/some-class.php', $tempPath), $files[4]->__toString());
+        $this->assertSame(sprintf('%s/composer.json', $expectedBaseDir), $files[0]->__toString());
+        $this->assertSame(sprintf('%s/nested/another-class.php', $expectedBaseDir), $files[1]->__toString());
+        $this->assertSame(sprintf('%s/nested/deep/even-more.php', $expectedBaseDir), $files[2]->__toString());
+        $this->assertSame(sprintf('%s/solution.php', $expectedBaseDir), $files[3]->__toString());
+        $this->assertSame(sprintf('%s/some-class.php', $expectedBaseDir), $files[4]->__toString());
 
         unlink(sprintf('%s/solution.php', $tempPath));
         unlink(sprintf('%s/some-class.php', $tempPath));
@@ -152,6 +176,14 @@ public function testWithNestedDirectories(): void
         rmdir(sprintf('%s/nested/deep', $tempPath));
         rmdir(sprintf('%s/nested', $tempPath));
         rmdir($tempPath);
+        unlink(sprintf('%s/solution.php', $expectedBaseDir));
+        unlink(sprintf('%s/some-class.php', $expectedBaseDir));
+        unlink(sprintf('%s/composer.json', $expectedBaseDir));
+        unlink(sprintf('%s/nested/another-class.php', $expectedBaseDir));
+        unlink(sprintf('%s/nested/deep/even-more.php', $expectedBaseDir));
+        rmdir(sprintf('%s/nested/deep', $expectedBaseDir));
+        rmdir(sprintf('%s/nested', $expectedBaseDir));
+        rmdir($expectedBaseDir);
     }
 
     public function testExceptionsWithNestedDirectories(): void
@@ -175,12 +207,14 @@ public function testExceptionsWithNestedDirectories(): void
 
         $solution = DirectorySolution::fromDirectory($tempPath, $exclusions);
 
-        $this->assertSame(sprintf('%s/solution.php', $tempPath), $solution->getEntryPoint());
+        $expectedBaseDir = SolutionPathTransformer::tempPathToSolutionTempPath($tempPath);
+
+        $this->assertSame(sprintf('%s/solution.php', $expectedBaseDir), $solution->getEntryPoint());
         $files = $solution->getFiles();
         $this->assertCount(2, $files);
 
-        $this->assertSame(sprintf('%s/solution.php', $tempPath), $files[0]->__toString());
-        $this->assertSame(sprintf('%s/some-class.php', $tempPath), $files[1]->__toString());
+        $this->assertSame(sprintf('%s/solution.php', $expectedBaseDir), $files[0]->__toString());
+        $this->assertSame(sprintf('%s/some-class.php', $expectedBaseDir), $files[1]->__toString());
 
         unlink(sprintf('%s/solution.php', $tempPath));
         unlink(sprintf('%s/some-class.php', $tempPath));
@@ -193,5 +227,16 @@ public function testExceptionsWithNestedDirectories(): void
         rmdir(sprintf('%s/vendor/somelib', $tempPath));
         rmdir(sprintf('%s/vendor', $tempPath));
         rmdir($tempPath);
+        unlink(sprintf('%s/solution.php', $expectedBaseDir));
+        unlink(sprintf('%s/some-class.php', $expectedBaseDir));
+        unlink(sprintf('%s/exclude.txt', $expectedBaseDir));
+        unlink(sprintf('%s/nested/exclude.txt', $expectedBaseDir));
+        unlink(sprintf('%s/nested/deep/exclude.txt', $expectedBaseDir));
+        unlink(sprintf('%s/vendor/somelib/app.php', $expectedBaseDir));
+        rmdir(sprintf('%s/nested/deep', $expectedBaseDir));
+        rmdir(sprintf('%s/nested', $expectedBaseDir));
+        rmdir(sprintf('%s/vendor/somelib', $expectedBaseDir));
+        rmdir(sprintf('%s/vendor', $expectedBaseDir));
+        rmdir($expectedBaseDir);
     }
 }
diff --git a/test/Solution/SingleFileSolutionTest.php b/test/Solution/SingleFileSolutionTest.php
index 6fa336d7..23ea19f9 100644
--- a/test/Solution/SingleFileSolutionTest.php
+++ b/test/Solution/SingleFileSolutionTest.php
@@ -3,13 +3,15 @@
 namespace PhpSchool\PhpWorkshopTest\Solution;
 
 use PhpSchool\PhpWorkshop\Solution\SingleFileSolution;
+use PhpSchool\PhpWorkshop\TestUtils\SolutionPathTransformer;
 use PHPUnit\Framework\TestCase;
 
 class SingleFileSolutionTest extends TestCase
 {
     public function testGetters(): void
     {
-        $tempPath   = sprintf('%s/%s', realpath(sys_get_temp_dir()), $this->getName());
+        $tmpDir = realpath(sys_get_temp_dir());
+        $tempPath   = sprintf('%s/%s', $tmpDir, $this->getName());
         $filePath   = sprintf('%s/test.file', $tempPath);
 
         @mkdir($tempPath, 0775, true);
@@ -17,11 +19,14 @@ public function testGetters(): void
 
         $solution = SingleFileSolution::fromFile($filePath);
 
-        $this->assertSame($filePath, $solution->getEntryPoint());
-        $this->assertSame($tempPath, $solution->getBaseDirectory());
+        $expectedBaseDir = SolutionPathTransformer::tempPathToSolutionTempPath($tempPath);
+        $expectedFilePath = SolutionPathTransformer::tempPathToSolutionTempPath($filePath);
+
+        $this->assertSame($expectedFilePath, $solution->getEntryPoint());
+        $this->assertSame($expectedBaseDir, $solution->getBaseDirectory());
         $this->assertFalse($solution->hasComposerFile());
         $this->assertCount(1, $solution->getFiles());
-        $this->assertSame($filePath, $solution->getFiles()[0]->__toString());
+        $this->assertSame($expectedFilePath, $solution->getFiles()[0]->__toString());
         unlink($filePath);
         rmdir($tempPath);
     }
diff --git a/test/Util/SystemTest.php b/test/Util/SystemTest.php
new file mode 100644
index 00000000..392fe111
--- /dev/null
+++ b/test/Util/SystemTest.php
@@ -0,0 +1,29 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpSchool\PhpWorkshopTest\Util;
+
+use PhpSchool\PhpWorkshop\Utils\System;
+use PHPUnit\Framework\TestCase;
+
+class SystemTest extends TestCase
+{
+    public function testRealpathThrowsOnFailure()
+    {
+        $this->expectException(\RuntimeException::class);
+        $this->expectExceptionMessage('Failed to get realpath of "non_existing_file.txt"');
+
+        System::realpath('non_existing_file.txt');
+    }
+
+    public function testRealpathReturnsFullPath()
+    {
+        self::assertSame(realpath(__DIR__), System::realpath(__DIR__));
+    }
+
+    public function testTempDir()
+    {
+        self::assertSame(realpath(sys_get_temp_dir()), System::tempDir());
+    }
+}