diff --git a/app/config.php b/app/config.php
index f61dbd34..7d5c4ddc 100644
--- a/app/config.php
+++ b/app/config.php
@@ -69,9 +69,9 @@
 use PhpSchool\PhpWorkshop\Output\OutputInterface;
 use PhpSchool\PhpWorkshop\Output\StdOutput;
 use PhpSchool\PhpWorkshop\Patch;
-use PhpSchool\PhpWorkshop\Process\DockerProcessFactory;
-use PhpSchool\PhpWorkshop\Process\HostProcessFactory;
-use PhpSchool\PhpWorkshop\Process\ProcessFactory;
+use PhpSchool\PhpWorkshop\Process\DockerSandbox;
+use PhpSchool\PhpWorkshop\Process\HostSandbox;
+use PhpSchool\PhpWorkshop\Process\Sandbox;
 use PhpSchool\PhpWorkshop\Result\Cgi\CgiResult;
 use PhpSchool\PhpWorkshop\Result\Cgi\GenericFailure as CgiGenericFailure;
 use PhpSchool\PhpWorkshop\Result\Cgi\RequestFailure as CgiRequestFailure;
@@ -195,28 +195,28 @@
         $manager = new RunnerManager();
         $manager->addFactory(new CliRunnerFactory(
             $c->get(EventDispatcher::class),
-            $c->get(ProcessFactory::class),
+            $c->get(Sandbox::class),
             $c->get(EnvironmentManager::class),
         ));
         $manager->addFactory(new CgiRunnerFactory(
             $c->get(EventDispatcher::class),
-            $c->get(ProcessFactory::class),
+            $c->get(Sandbox::class),
             $c->get(EnvironmentManager::class),
         ));
         $manager->addFactory(new CustomVerifyingRunnerFactory());
         return $manager;
     },
 
-    ProcessFactory::class => function (ContainerInterface $c) {
-        $processFactory = getenv('PROCESS_FACTORY');
+    Sandbox::class => function (ContainerInterface $c) {
+        $sandbox = getenv('SANDBOX');
 
-        return match ($processFactory) {
-            'docker' => new DockerProcessFactory(
+        return match ($sandbox) {
+            'docker' => new DockerSandbox(
                 $c->get('basePath'),
                 $c->get('appName'),
                 $c->get('phpschoolGlobalDir') . '/composer-cache',
             ),
-            default => new HostProcessFactory(),
+            default => new HostSandbox(),
         };
     },
 
@@ -278,7 +278,7 @@
     },
     PrepareSolutionListener::class => function (ContainerInterface $c) {
         return new PrepareSolutionListener(
-            $c->get(ProcessFactory::class),
+            $c->get(Sandbox::class),
         );
     },
     CodePatchListener::class => function (ContainerInterface $c) {
diff --git a/src/Exception/CodeExecutionException.php b/src/Exception/CodeExecutionException.php
index aff5c67a..fbff58be 100644
--- a/src/Exception/CodeExecutionException.php
+++ b/src/Exception/CodeExecutionException.php
@@ -5,7 +5,7 @@
 namespace PhpSchool\PhpWorkshop\Exception;
 
 use RuntimeException;
-use Symfony\Component\Process\Process;
+use PhpSchool\PhpWorkshop\Process\SandboxExecution;
 
 /**
  * Represents the situation where some PHP code could not be executed successfully.
@@ -13,17 +13,16 @@
 class CodeExecutionException extends RuntimeException
 {
     /**
-     * Static constructor to create an instance from a failed `Symfony\Component\Process\Process` instance.
+     * Static constructor to create an instance from a failed sandbox execution.
      *
-     * @param Process $process The `Symfony\Component\Process\Process` instance which failed.
      * @return self
      */
-    public static function fromProcess(Process $process): self
+    public static function fromExecution(SandboxExecution $execution): self
     {
         return new self(
             sprintf(
                 'PHP Code failed to execute. Error: "%s"',
-                trim($process->getErrorOutput() ?: $process->getOutput()),
+                trim($execution->getErrorOutput() ?: $execution->getOutput()),
             ),
         );
     }
diff --git a/src/ExerciseRunner/CgiRunner.php b/src/ExerciseRunner/CgiRunner.php
index 8b42fd36..981a9602 100644
--- a/src/ExerciseRunner/CgiRunner.php
+++ b/src/ExerciseRunner/CgiRunner.php
@@ -21,8 +21,9 @@
 use PhpSchool\PhpWorkshop\ExerciseRunner\Context\ExecutionContext;
 use PhpSchool\PhpWorkshop\Input\Input;
 use PhpSchool\PhpWorkshop\Output\OutputInterface;
-use PhpSchool\PhpWorkshop\Process\ProcessFactory;
+use PhpSchool\PhpWorkshop\Process\Sandbox;
 use PhpSchool\PhpWorkshop\Process\ProcessInput;
+use PhpSchool\PhpWorkshop\Process\SandboxExecution;
 use PhpSchool\PhpWorkshop\Result\Cgi\CgiResult;
 use PhpSchool\PhpWorkshop\Result\Cgi\RequestFailure;
 use PhpSchool\PhpWorkshop\Result\Cgi\GenericFailure;
@@ -31,7 +32,6 @@
 use PhpSchool\PhpWorkshop\Result\ResultInterface;
 use Psr\Http\Message\RequestInterface;
 use Psr\Http\Message\ResponseInterface;
-use Symfony\Component\Process\Process;
 
 /**
  * The `CGI` runner. This runner executes solutions as if they were behind a web-server. They populate the `$_SERVER`,
@@ -59,7 +59,7 @@ class CgiRunner implements ExerciseRunnerInterface
     public function __construct(
         private CgiExercise $exercise,
         private EventDispatcher $eventDispatcher,
-        private ProcessFactory $processFactory,
+        private Sandbox $sandbox,
         private EnvironmentManager $environmentManager,
     ) {}
 
@@ -215,21 +215,21 @@ private function executePhpFile(
         RequestInterface $request,
         string $type,
     ): ResponseInterface {
-        $process = $this->getPhpProcess($workingDirectory, $fileName, $request, $scenario->getExposedPorts());
+        $execution = $this->getPhpExecution($workingDirectory, $fileName, $request, $scenario->getExposedPorts());
 
-        $process->start();
+        $execution->start();
         $this->eventDispatcher->dispatch(
             new CgiExecuteEvent(sprintf('cgi.verify.%s.executing', $type), $context, $scenario, $request),
         );
-        $process->wait();
+        $execution->wait();
 
-        if (!$process->isSuccessful()) {
-            throw CodeExecutionException::fromProcess($process);
+        if (!$execution->isSuccessful()) {
+            throw CodeExecutionException::fromExecution($execution);
         }
 
         //if no status line, pre-pend 200 OK
-        $output = $process->getOutput();
-        $error = $process->getErrorOutput();
+        $output = $execution->getOutput();
+        $error = $execution->getErrorOutput();
         if (!preg_match('/^HTTP\/([1-9]\d*\.\d) ([1-5]\d{2})(\s+(.+))?\\r\\n/', $output)) {
             $output = "HTTP/1.0 200 OK\r\n" . $output;
         }
@@ -240,7 +240,7 @@ private function executePhpFile(
     /**
      * @param list<int> $exposedPorts
      */
-    private function getPhpProcess(string $workingDirectory, string $fileName, RequestInterface $request, array $exposedPorts): Process
+    private function getPhpExecution(string $workingDirectory, string $fileName, RequestInterface $request, array $exposedPorts): SandboxExecution
     {
         $env = [
             'REQUEST_METHOD'  => $request->getMethod(),
@@ -272,7 +272,7 @@ private function getPhpProcess(string $workingDirectory, string $fileName, Reque
             $content,
         );
 
-        return $this->processFactory->create($processInput);
+        return $this->sandbox->create($processInput);
     }
 
     /**
@@ -308,14 +308,14 @@ public function run(ExecutionContext $context, OutputInterface $output): bool
             $event = $this->eventDispatcher->dispatch(
                 new CgiExecuteEvent('cgi.run.student-execute.pre', $context, $scenario, $request),
             );
-            $process = $this->getPhpProcess(
+            $execution = $this->getPhpExecution(
                 $context->getStudentExecutionDirectory(),
                 basename($context->getEntryPoint()),
                 $event->getRequest(),
                 $scenario->getExposedPorts(),
             );
 
-            $process->start();
+            $execution->start();
             $this->eventDispatcher->dispatch(
                 new CgiExecuteEvent(
                     'cgi.run.student.executing',
@@ -325,12 +325,12 @@ public function run(ExecutionContext $context, OutputInterface $output): bool
                     ['output' => $output],
                 ),
             );
-            $process->wait(function ($outputType, $outputBuffer) use ($output) {
+            $execution->wait(function ($outputType, $outputBuffer) use ($output) {
                 $output->write($outputBuffer);
             });
             $output->emptyLine();
 
-            if (!$process->isSuccessful()) {
+            if (!$execution->isSuccessful()) {
                 $success = false;
             }
 
diff --git a/src/ExerciseRunner/CliRunner.php b/src/ExerciseRunner/CliRunner.php
index 3bbeadb2..0dab8b1b 100644
--- a/src/ExerciseRunner/CliRunner.php
+++ b/src/ExerciseRunner/CliRunner.php
@@ -20,8 +20,9 @@
 use PhpSchool\PhpWorkshop\ExerciseRunner\Context\ExecutionContext;
 use PhpSchool\PhpWorkshop\Input\Input;
 use PhpSchool\PhpWorkshop\Output\OutputInterface;
-use PhpSchool\PhpWorkshop\Process\ProcessFactory;
+use PhpSchool\PhpWorkshop\Process\Sandbox;
 use PhpSchool\PhpWorkshop\Process\ProcessInput;
+use PhpSchool\PhpWorkshop\Process\SandboxExecution;
 use PhpSchool\PhpWorkshop\Result\Cli\RequestFailure;
 use PhpSchool\PhpWorkshop\Result\Cli\CliResult;
 use PhpSchool\PhpWorkshop\Result\Cli\GenericFailure;
@@ -29,7 +30,6 @@
 use PhpSchool\PhpWorkshop\Result\Cli\ResultInterface as CliResultInterface;
 use PhpSchool\PhpWorkshop\Result\ResultInterface;
 use PhpSchool\PhpWorkshop\Utils\Collection;
-use Symfony\Component\Process\Process;
 
 /**
  * The `CLI` runner. This runner executes solutions as PHP CLI scripts, passing the arguments
@@ -59,7 +59,7 @@ class CliRunner implements ExerciseRunnerInterface
     public function __construct(
         private CliExercise $exercise,
         private EventDispatcher $eventDispatcher,
-        private ProcessFactory $processFactory,
+        private Sandbox $sandbox,
         private EnvironmentManager $environmentManager,
     ) {}
 
@@ -220,24 +220,24 @@ public function run(ExecutionContext $context, OutputInterface $output): bool
 
             $args = $event->getArgs();
 
-            $process = $this->getPhpProcess(
+            $execution = $this->getPhpExecution(
                 $context->getStudentExecutionDirectory(),
                 basename($context->getEntryPoint()),
                 $args,
                 $scenario->getExposedPorts(),
             );
 
-            $process->start();
+            $execution->start();
             $this->eventDispatcher->dispatch(
                 new CliExecuteEvent('cli.run.student.executing', $context, $scenario, $args, ['output' => $output]),
             );
-            $process->wait(function ($outputType, $outputBuffer) use ($output) {
+            $execution->wait(function ($outputType, $outputBuffer) use ($output) {
                 $output->write($outputBuffer);
             });
 
             $output->emptyLine();
 
-            if (!$process->isSuccessful()) {
+            if (!$execution->isSuccessful()) {
                 $success = false;
             }
 
@@ -258,28 +258,28 @@ public function run(ExecutionContext $context, OutputInterface $output): bool
      */
     private function executePhpFile(ExecutionContext $context, CliScenario $scenario, string $workingDirectory, string $fileName, Collection $args, string $type): string
     {
-        $process = $this->getPhpProcess($workingDirectory, $fileName, $args, $scenario->getExposedPorts());
+        $execution = $this->getPhpExecution($workingDirectory, $fileName, $args, $scenario->getExposedPorts());
 
-        $process->start();
+        $execution->start();
         $this->eventDispatcher->dispatch(
             new CliExecuteEvent(sprintf('cli.verify.%s.executing', $type), $context, $scenario, $args),
         );
-        $process->wait();
+        $execution->wait();
 
-        if (!$process->isSuccessful()) {
-            throw CodeExecutionException::fromProcess($process);
+        if (!$execution->isSuccessful()) {
+            throw CodeExecutionException::fromExecution($execution);
         }
 
-        return $process->getOutput();
+        return $execution->getOutput();
     }
 
     /**
      * @param Collection<int, string> $args
      * @param list<int> $exposedPorts
      */
-    private function getPhpProcess(string $workingDirectory, string $fileName, Collection $args, array $exposedPorts): Process
+    private function getPhpExecution(string $workingDirectory, string $fileName, Collection $args, array $exposedPorts): SandboxExecution
     {
-        return $this->processFactory->create(
+        return $this->sandbox->create(
             new ProcessInput('php', [$fileName, ...$args->getArrayCopy()], $workingDirectory, [], $exposedPorts),
         );
     }
diff --git a/src/ExerciseRunner/Factory/CgiRunnerFactory.php b/src/ExerciseRunner/Factory/CgiRunnerFactory.php
index a53fec95..52eebeb9 100644
--- a/src/ExerciseRunner/Factory/CgiRunnerFactory.php
+++ b/src/ExerciseRunner/Factory/CgiRunnerFactory.php
@@ -13,7 +13,7 @@
 use PhpSchool\PhpWorkshop\ExerciseRunner\CgiRunner;
 use PhpSchool\PhpWorkshop\ExerciseRunner\EnvironmentManager;
 use PhpSchool\PhpWorkshop\ExerciseRunner\ExerciseRunnerInterface;
-use PhpSchool\PhpWorkshop\Process\ProcessFactory;
+use PhpSchool\PhpWorkshop\Process\Sandbox;
 
 /**
  * Factory class for `CgiRunner`
@@ -25,7 +25,7 @@ class CgiRunnerFactory implements ExerciseRunnerFactoryInterface
      */
     private static string $type = ExerciseType::CGI;
 
-    public function __construct(private EventDispatcher $eventDispatcher, private ProcessFactory $processFactory, private EnvironmentManager $environmentManager) {}
+    public function __construct(private EventDispatcher $eventDispatcher, private Sandbox $sandbox, private EnvironmentManager $environmentManager) {}
 
     /**
      * Whether the factory supports this exercise type.
@@ -56,6 +56,6 @@ public function configureInput(CommandDefinition $commandDefinition): void
      */
     public function create(ExerciseInterface $exercise): ExerciseRunnerInterface
     {
-        return new CgiRunner($exercise, $this->eventDispatcher, $this->processFactory, $this->environmentManager);
+        return new CgiRunner($exercise, $this->eventDispatcher, $this->sandbox, $this->environmentManager);
     }
 }
diff --git a/src/ExerciseRunner/Factory/CliRunnerFactory.php b/src/ExerciseRunner/Factory/CliRunnerFactory.php
index 4ee13f18..8a584d16 100644
--- a/src/ExerciseRunner/Factory/CliRunnerFactory.php
+++ b/src/ExerciseRunner/Factory/CliRunnerFactory.php
@@ -13,7 +13,7 @@
 use PhpSchool\PhpWorkshop\ExerciseRunner\CliRunner;
 use PhpSchool\PhpWorkshop\ExerciseRunner\EnvironmentManager;
 use PhpSchool\PhpWorkshop\ExerciseRunner\ExerciseRunnerInterface;
-use PhpSchool\PhpWorkshop\Process\ProcessFactory;
+use PhpSchool\PhpWorkshop\Process\Sandbox;
 
 /**
  * Factory class for `CliRunner`
@@ -25,7 +25,7 @@ class CliRunnerFactory implements ExerciseRunnerFactoryInterface
      */
     private static string $type = ExerciseType::CLI;
 
-    public function __construct(private EventDispatcher $eventDispatcher, private ProcessFactory $processFactory, private EnvironmentManager $environmentManager) {}
+    public function __construct(private EventDispatcher $eventDispatcher, private Sandbox $sandbox, private EnvironmentManager $environmentManager) {}
 
     /**
      * Whether the factory supports this exercise type.
@@ -56,6 +56,6 @@ public function configureInput(CommandDefinition $commandDefinition): void
      */
     public function create(ExerciseInterface $exercise): ExerciseRunnerInterface
     {
-        return new CliRunner($exercise, $this->eventDispatcher, $this->processFactory, $this->environmentManager);
+        return new CliRunner($exercise, $this->eventDispatcher, $this->sandbox, $this->environmentManager);
     }
 }
diff --git a/src/Listener/PrepareSolutionListener.php b/src/Listener/PrepareSolutionListener.php
index 620b4562..65d3a396 100644
--- a/src/Listener/PrepareSolutionListener.php
+++ b/src/Listener/PrepareSolutionListener.php
@@ -7,7 +7,7 @@
 use PhpSchool\PhpWorkshop\Event\ExerciseRunnerEvent;
 use PhpSchool\PhpWorkshop\Exercise\ProvidesSolution;
 use PhpSchool\PhpWorkshop\Exception\RuntimeException;
-use PhpSchool\PhpWorkshop\Process\ProcessFactory;
+use PhpSchool\PhpWorkshop\Process\Sandbox;
 use PhpSchool\PhpWorkshop\Process\ProcessInput;
 
 /**
@@ -15,9 +15,9 @@
  */
 class PrepareSolutionListener
 {
-    public function __construct(private ProcessFactory $processFactory)
+    public function __construct(private Sandbox $sandbox)
     {
-        $this->processFactory = $processFactory;
+        $this->sandbox = $sandbox;
     }
 
     /**
@@ -40,12 +40,12 @@ public function __invoke(ExerciseRunnerEvent $event): void
         //prepare composer deps
         //only install if vendor folder not available
         if (!file_exists(sprintf('%s/vendor', $event->getContext()->getReferenceExecutionDirectory()))) {
-            $process = $this->processFactory->create(
+            $execution = $this->sandbox->create(
                 new ProcessInput('composer', ['install', '--no-interaction'], $event->getContext()->getReferenceExecutionDirectory(), [], []),
             );
 
             try {
-                $process->mustRun();
+                $execution->mustRun();
             } catch (\Symfony\Component\Process\Exception\RuntimeException $e) {
                 throw new RuntimeException('Composer dependencies could not be installed', 0, $e);
             }
diff --git a/src/Process/DockerExecution.php b/src/Process/DockerExecution.php
new file mode 100644
index 00000000..d7ea71a8
--- /dev/null
+++ b/src/Process/DockerExecution.php
@@ -0,0 +1,75 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpSchool\PhpWorkshop\Process;
+
+use Symfony\Component\Process\Exception\ProcessFailedException;
+use Symfony\Component\Process\Process;
+
+/**
+ * The main process plus the docker steps around it, eg. `create` and `cp` before, `rm` after.
+ */
+final class DockerExecution implements SandboxExecution
+{
+    /**
+     * @param list<Process> $before
+     * @param list<Process> $after
+     */
+    public function __construct(
+        public readonly Process $process,
+        public readonly array $before = [],
+        public readonly array $after = [],
+    ) {}
+
+    public function start(): void
+    {
+        foreach ($this->before as $step) {
+            $step->mustRun();
+        }
+
+        $this->process->start();
+    }
+
+    public function wait(?callable $callback = null): int
+    {
+        try {
+            return $this->process->wait($callback);
+        } finally {
+            $this->runAfter();
+        }
+    }
+
+    public function mustRun(): void
+    {
+        $this->start();
+        $this->wait();
+
+        if (!$this->process->isSuccessful()) {
+            throw new ProcessFailedException($this->process);
+        }
+    }
+
+    public function isSuccessful(): bool
+    {
+        return $this->process->isSuccessful();
+    }
+
+    public function getOutput(): string
+    {
+        return $this->process->getOutput();
+    }
+
+    public function getErrorOutput(): string
+    {
+        return $this->process->getErrorOutput();
+    }
+
+    private function runAfter(): void
+    {
+        foreach ($this->after as $step) {
+            //cleanup, so keep going if one fails
+            $step->run();
+        }
+    }
+}
diff --git a/src/Process/DockerProcessFactory.php b/src/Process/DockerSandbox.php
similarity index 94%
rename from src/Process/DockerProcessFactory.php
rename to src/Process/DockerSandbox.php
index 26eaeeb3..ffc253f8 100644
--- a/src/Process/DockerProcessFactory.php
+++ b/src/Process/DockerSandbox.php
@@ -12,7 +12,7 @@
  *
  * The workshop only supplies the image. All isolation flags are set here so a workshop cannot loosen them.
  */
-final class DockerProcessFactory implements ProcessFactory
+final class DockerSandbox implements Sandbox
 {
     private const TIMEOUT = 30;
 
@@ -57,7 +57,7 @@ public function createBuildProcess(): Process
         );
     }
 
-    public function create(ProcessInput $processInput): Process
+    public function create(ProcessInput $processInput): DockerExecution
     {
         $isComposer = $processInput->getExecutable() === 'composer';
 
@@ -89,7 +89,8 @@ public function create(ProcessInput $processInput): Process
             $envArgs[] = $key . '=' . $value;
         }
 
-        return new Process(
+        //no steps around it yet, create/cp/rm come when files are copied in instead of mounted
+        return new DockerExecution(new Process(
             [
                 $this->findDocker(),
                 'run',
@@ -131,7 +132,7 @@ public function create(ProcessInput $processInput): Process
             null,
             $processInput->getInput(),
             self::TIMEOUT + 5,
-        );
+        ));
     }
 
     private function findDocker(): string
diff --git a/src/Process/HostExecution.php b/src/Process/HostExecution.php
new file mode 100644
index 00000000..9694349c
--- /dev/null
+++ b/src/Process/HostExecution.php
@@ -0,0 +1,42 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpSchool\PhpWorkshop\Process;
+
+use Symfony\Component\Process\Process;
+
+final class HostExecution implements SandboxExecution
+{
+    public function __construct(public readonly Process $process) {}
+
+    public function start(): void
+    {
+        $this->process->start();
+    }
+
+    public function wait(?callable $callback = null): int
+    {
+        return $this->process->wait($callback);
+    }
+
+    public function mustRun(): void
+    {
+        $this->process->mustRun();
+    }
+
+    public function isSuccessful(): bool
+    {
+        return $this->process->isSuccessful();
+    }
+
+    public function getOutput(): string
+    {
+        return $this->process->getOutput();
+    }
+
+    public function getErrorOutput(): string
+    {
+        return $this->process->getErrorOutput();
+    }
+}
diff --git a/src/Process/HostProcessFactory.php b/src/Process/HostSandbox.php
similarity index 90%
rename from src/Process/HostProcessFactory.php
rename to src/Process/HostSandbox.php
index af7196d8..2154ef08 100644
--- a/src/Process/HostProcessFactory.php
+++ b/src/Process/HostSandbox.php
@@ -7,7 +7,7 @@
 use Symfony\Component\Process\ExecutableFinder;
 use Symfony\Component\Process\Process;
 
-final class HostProcessFactory implements ProcessFactory
+final class HostSandbox implements Sandbox
 {
     /**
      * Inherited env vars that are kept, everything else is unset so we don't leak secrets to the process
@@ -22,7 +22,7 @@ public function __construct(?ExecutableFinder $executableFinder = null)
     }
 
 
-    public function create(ProcessInput $processInput): Process
+    public function create(ProcessInput $processInput): HostExecution
     {
         $executablePath = $this->executableFinder->find($processInput->getExecutable());
 
@@ -30,13 +30,13 @@ public function create(ProcessInput $processInput): Process
             throw ProcessNotFoundException::fromExecutable($processInput->getExecutable());
         }
 
-        return new Process(
+        return new HostExecution(new Process(
             [$executablePath, ...$processInput->getArgs()],
             $processInput->getWorkingDirectory(),
             array_merge($this->getDefaultEnv(), $processInput->getEnv()),
             $processInput->getInput(),
             10,
-        );
+        ));
     }
 
     /**
diff --git a/src/Process/ProcessFactory.php b/src/Process/ProcessFactory.php
deleted file mode 100644
index 8e7faffa..00000000
--- a/src/Process/ProcessFactory.php
+++ /dev/null
@@ -1,12 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace PhpSchool\PhpWorkshop\Process;
-
-use Symfony\Component\Process\Process;
-
-interface ProcessFactory
-{
-    public function create(ProcessInput $processInput): Process;
-}
diff --git a/src/Process/Sandbox.php b/src/Process/Sandbox.php
new file mode 100644
index 00000000..784281f4
--- /dev/null
+++ b/src/Process/Sandbox.php
@@ -0,0 +1,10 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpSchool\PhpWorkshop\Process;
+
+interface Sandbox
+{
+    public function create(ProcessInput $processInput): SandboxExecution;
+}
diff --git a/src/Process/SandboxExecution.php b/src/Process/SandboxExecution.php
new file mode 100644
index 00000000..f0638945
--- /dev/null
+++ b/src/Process/SandboxExecution.php
@@ -0,0 +1,29 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpSchool\PhpWorkshop\Process;
+
+/**
+ * One run of some code in a sandbox. How many commands that takes is up to the sandbox.
+ */
+interface SandboxExecution
+{
+    public function start(): void;
+
+    /**
+     * @param (callable(string, string): void)|null $callback receives the output as it comes
+     */
+    public function wait(?callable $callback = null): int;
+
+    /**
+     * @throws \Symfony\Component\Process\Exception\ProcessFailedException if it fails
+     */
+    public function mustRun(): void;
+
+    public function isSuccessful(): bool;
+
+    public function getOutput(): string;
+
+    public function getErrorOutput(): string;
+}
diff --git a/test/Check/DatabaseCheckTest.php b/test/Check/DatabaseCheckTest.php
index 7ff48326..a16edf80 100644
--- a/test/Check/DatabaseCheckTest.php
+++ b/test/Check/DatabaseCheckTest.php
@@ -16,7 +16,7 @@
 use PhpSchool\PhpWorkshop\ExerciseRunner\RunnerManager;
 use PhpSchool\PhpWorkshop\Input\Input;
 use PhpSchool\PhpWorkshop\Output\BufferedOutput;
-use PhpSchool\PhpWorkshop\Process\HostProcessFactory;
+use PhpSchool\PhpWorkshop\Process\HostSandbox;
 use PhpSchool\PhpWorkshop\ResultAggregator;
 use PhpSchool\PhpWorkshop\Solution\SingleFileSolution;
 use PhpSchool\PhpWorkshopTest\Asset\DatabaseExercise;
@@ -56,7 +56,7 @@ public function testCheckMeta(): void
     private function getRunnerManager(ExerciseInterface $exercise, EventDispatcher $eventDispatcher): MockObject
     {
         $runner = $this->getMockBuilder(CliRunner::class)
-            ->setConstructorArgs([$exercise, $eventDispatcher, new HostProcessFactory(), new EnvironmentManager(new Filesystem(), $eventDispatcher)])
+            ->setConstructorArgs([$exercise, $eventDispatcher, new HostSandbox(), new EnvironmentManager(new Filesystem(), $eventDispatcher)])
             ->onlyMethods(['getRequiredChecks'])
             ->getMock();
 
diff --git a/test/Exception/CodeExecutionExceptionTest.php b/test/Exception/CodeExecutionExceptionTest.php
index f774c481..63788ba2 100644
--- a/test/Exception/CodeExecutionExceptionTest.php
+++ b/test/Exception/CodeExecutionExceptionTest.php
@@ -4,7 +4,7 @@
 
 use PhpSchool\PhpWorkshop\Exception\CodeExecutionException;
 use PHPUnit\Framework\TestCase;
-use Symfony\Component\Process\Process;
+use PhpSchool\PhpWorkshop\Process\SandboxExecution;
 
 class CodeExecutionExceptionTest extends TestCase
 {
@@ -16,20 +16,20 @@ public function testException(): void
 
     public function testFromProcessUsesErrorOutputIfNotEmpty(): void
     {
-        $process = $this->createMock(Process::class);
+        $process = $this->createMock(SandboxExecution::class);
 
         $process
             ->expects($this->once())
             ->method('getErrorOutput')
             ->willReturn('Error Output');
 
-        $e = CodeExecutionException::fromProcess($process);
+        $e = CodeExecutionException::fromExecution($process);
         $this->assertEquals('PHP Code failed to execute. Error: "Error Output"', $e->getMessage());
     }
 
     public function testFromProcessUsesStdOutputIfErrorOutputEmpty(): void
     {
-        $process = $this->createMock(Process::class);
+        $process = $this->createMock(SandboxExecution::class);
         $process
             ->expects($this->once())
             ->method('getErrorOutput')
@@ -40,7 +40,7 @@ public function testFromProcessUsesStdOutputIfErrorOutputEmpty(): void
             ->method('getOutput')
             ->willReturn('Std Output');
 
-        $e = CodeExecutionException::fromProcess($process);
+        $e = CodeExecutionException::fromExecution($process);
         $this->assertEquals('PHP Code failed to execute. Error: "Std Output"', $e->getMessage());
     }
 }
diff --git a/test/ExerciseRunner/CgiRunnerTest.php b/test/ExerciseRunner/CgiRunnerTest.php
index d8ce0de1..ff9cb020 100644
--- a/test/ExerciseRunner/CgiRunnerTest.php
+++ b/test/ExerciseRunner/CgiRunnerTest.php
@@ -9,7 +9,7 @@
 use PhpSchool\PhpWorkshop\ExerciseRunner\Context\TestContext;
 use PhpSchool\PhpWorkshop\ExerciseRunner\EnvironmentManager;
 use PhpSchool\PhpWorkshop\Listener\OutputRunInfoListener;
-use PhpSchool\PhpWorkshop\Process\HostProcessFactory;
+use PhpSchool\PhpWorkshop\Process\HostSandbox;
 use PhpSchool\PhpWorkshopTest\Asset\CgiExerciseImpl;
 use PhpSchool\Terminal\Terminal;
 use PhpSchool\PhpWorkshop\Check\CodeParseCheck;
@@ -38,7 +38,7 @@ public function setUp(): void
     {
         $this->exercise = new CgiExerciseImpl();
         $this->eventDispatcher = new EventDispatcher(new ResultAggregator());
-        $this->runner = new CgiRunner($this->exercise, $this->eventDispatcher, new HostProcessFactory(), new EnvironmentManager(new Filesystem(), $this->eventDispatcher));
+        $this->runner = new CgiRunner($this->exercise, $this->eventDispatcher, new HostSandbox(), new EnvironmentManager(new Filesystem(), $this->eventDispatcher));
 
         $this->assertEquals('CGI Program Runner', $this->runner->getName());
     }
diff --git a/test/ExerciseRunner/CliRunnerTest.php b/test/ExerciseRunner/CliRunnerTest.php
index 3798fe57..b2f46c27 100644
--- a/test/ExerciseRunner/CliRunnerTest.php
+++ b/test/ExerciseRunner/CliRunnerTest.php
@@ -8,11 +8,11 @@
 use PhpSchool\PhpWorkshop\ExerciseRunner\Context\TestContext;
 use PhpSchool\PhpWorkshop\ExerciseRunner\EnvironmentManager;
 use PhpSchool\PhpWorkshop\Listener\OutputRunInfoListener;
-use PhpSchool\PhpWorkshop\Process\HostProcessFactory;
-use Symfony\Component\Process\Process;
+use PhpSchool\PhpWorkshop\Process\HostSandbox;
+use PhpSchool\PhpWorkshop\Process\SandboxExecution;
 use PhpSchool\PhpWorkshop\Output\NullOutput;
 use PhpSchool\PhpWorkshop\Process\ProcessInput;
-use PhpSchool\PhpWorkshop\Process\ProcessFactory;
+use PhpSchool\PhpWorkshop\Process\Sandbox;
 use PhpSchool\PhpWorkshop\Utils\RequestRenderer;
 use PhpSchool\PhpWorkshopTest\Asset\CliExerciseImpl;
 use PhpSchool\Terminal\Terminal;
@@ -42,7 +42,7 @@ public function setUp(): void
     {
         $this->exercise = new CliExerciseImpl();
         $this->eventDispatcher = new EventDispatcher(new ResultAggregator());
-        $this->runner = new CliRunner($this->exercise, $this->eventDispatcher, new HostProcessFactory(), new EnvironmentManager(new Filesystem(), $this->eventDispatcher));
+        $this->runner = new CliRunner($this->exercise, $this->eventDispatcher, new HostSandbox(), new EnvironmentManager(new Filesystem(), $this->eventDispatcher));
 
         $this->assertEquals('CLI Program Runner', $this->runner->getName());
     }
@@ -173,25 +173,25 @@ public function testRunPassesOutputAndReturnsSuccessIfScriptIsSuccessful(): void
     public function testRunPassesTheEntryPointRelativeToTheWorkingDirectory(): void
     {
         //the sandbox mounts the working directory at a different path, so a host path would not exist in there
-        $processFactory = new class implements ProcessFactory {
+        $sandbox = new class implements Sandbox {
             /** @var array<ProcessInput> */
             public array $inputs = [];
 
-            public function create(ProcessInput $processInput): Process
+            public function create(ProcessInput $processInput): SandboxExecution
             {
                 $this->inputs[] = $processInput;
 
-                return (new HostProcessFactory())->create($processInput);
+                return (new HostSandbox())->create($processInput);
             }
         };
-        $runner = new CliRunner($this->exercise, $this->eventDispatcher, $processFactory, new EnvironmentManager(new Filesystem(), $this->eventDispatcher));
+        $runner = new CliRunner($this->exercise, $this->eventDispatcher, $sandbox, new EnvironmentManager(new Filesystem(), $this->eventDispatcher));
 
         $this->exercise->setScenario((new CliScenario())->withExecution([1, 2, 3]));
 
         $context = TestContext::fromExerciseAndStudentSolution($this->exercise, __DIR__ . '/../res/cli/user.php');
         $runner->run($context, new NullOutput());
 
-        $this->assertSame('user.php', $processFactory->inputs[0]->getArgs()[0]);
+        $this->assertSame('user.php', $sandbox->inputs[0]->getArgs()[0]);
     }
 
     public function testRunPassesOutputAndReturnsFailureIfScriptFails(): void
diff --git a/test/ExerciseRunner/Factory/CgiRunnerFactoryTest.php b/test/ExerciseRunner/Factory/CgiRunnerFactoryTest.php
index 5010b80c..6bf45d40 100644
--- a/test/ExerciseRunner/Factory/CgiRunnerFactoryTest.php
+++ b/test/ExerciseRunner/Factory/CgiRunnerFactoryTest.php
@@ -9,7 +9,7 @@
 use PhpSchool\PhpWorkshop\ExerciseRunner\CgiRunner;
 use PhpSchool\PhpWorkshop\ExerciseRunner\EnvironmentManager;
 use PhpSchool\PhpWorkshop\ExerciseRunner\Factory\CgiRunnerFactory;
-use PhpSchool\PhpWorkshop\Process\HostProcessFactory;
+use PhpSchool\PhpWorkshop\Process\HostSandbox;
 use PhpSchool\PhpWorkshopTest\Asset\CgiExerciseImpl;
 use PHPUnit\Framework\TestCase;
 
@@ -21,7 +21,7 @@ class CgiRunnerFactoryTest extends TestCase
     public function setUp(): void
     {
         $this->eventDispatcher = $this->createMock(EventDispatcher::class);
-        $this->factory = new CgiRunnerFactory($this->eventDispatcher, new HostProcessFactory(), $this->createMock(EnvironmentManager::class));
+        $this->factory = new CgiRunnerFactory($this->eventDispatcher, new HostSandbox(), $this->createMock(EnvironmentManager::class));
     }
 
     public function testSupports(): void
diff --git a/test/ExerciseRunner/Factory/CliRunnerFactoryTest.php b/test/ExerciseRunner/Factory/CliRunnerFactoryTest.php
index ce5fe6f6..c057ef8d 100644
--- a/test/ExerciseRunner/Factory/CliRunnerFactoryTest.php
+++ b/test/ExerciseRunner/Factory/CliRunnerFactoryTest.php
@@ -9,7 +9,7 @@
 use PhpSchool\PhpWorkshop\ExerciseRunner\CliRunner;
 use PhpSchool\PhpWorkshop\ExerciseRunner\EnvironmentManager;
 use PhpSchool\PhpWorkshop\ExerciseRunner\Factory\CliRunnerFactory;
-use PhpSchool\PhpWorkshop\Process\HostProcessFactory;
+use PhpSchool\PhpWorkshop\Process\HostSandbox;
 use PhpSchool\PhpWorkshopTest\Asset\CliExerciseImpl;
 use PHPUnit\Framework\TestCase;
 
@@ -21,7 +21,7 @@ class CliRunnerFactoryTest extends TestCase
     public function setUp(): void
     {
         $this->eventDispatcher = $this->createMock(EventDispatcher::class);
-        $this->factory = new CliRunnerFactory($this->eventDispatcher, new HostProcessFactory(), $this->createMock(EnvironmentManager::class));
+        $this->factory = new CliRunnerFactory($this->eventDispatcher, new HostSandbox(), $this->createMock(EnvironmentManager::class));
     }
 
     public function testSupports(): void
diff --git a/test/Listener/PrepareSolutionListenerTest.php b/test/Listener/PrepareSolutionListenerTest.php
index 913035cd..ddd575b5 100644
--- a/test/Listener/PrepareSolutionListenerTest.php
+++ b/test/Listener/PrepareSolutionListenerTest.php
@@ -5,7 +5,7 @@
 use PhpSchool\PhpWorkshop\Event\ExerciseRunnerEvent;
 use PhpSchool\PhpWorkshop\ExerciseRunner\Context\TestContext;
 use PhpSchool\PhpWorkshop\Listener\PrepareSolutionListener;
-use PhpSchool\PhpWorkshop\Process\HostProcessFactory;
+use PhpSchool\PhpWorkshop\Process\HostSandbox;
 use PhpSchool\PhpWorkshop\Process\ProcessNotFoundException;
 use PhpSchool\PhpWorkshop\Solution\SolutionInterface;
 use PhpSchool\PhpWorkshopTest\Asset\CliExerciseImpl;
@@ -33,7 +33,7 @@ public function testIfSolutionRequiresComposerButComposerCannotBeLocatedExceptio
         $this->expectException(ProcessNotFoundException::class);
         $this->expectExceptionMessage('Could not find executable: "composer"');
         $event = new ExerciseRunnerEvent('event', $context);
-        (new PrepareSolutionListener(new HostProcessFactory($finder)))->__invoke($event);
+        (new PrepareSolutionListener(new HostSandbox($finder)))->__invoke($event);
     }
 
     public function testIfSolutionRequiresComposerButVendorDirExistsNothingIsDone(): void
@@ -54,7 +54,7 @@ public function testIfSolutionRequiresComposerButVendorDirExistsNothingIsDone():
         $exercise->setSolution($solution);
 
         $event = new ExerciseRunnerEvent('event', $context);
-        (new PrepareSolutionListener(new HostProcessFactory()))->__invoke($event);
+        (new PrepareSolutionListener(new HostSandbox()))->__invoke($event);
 
         $this->assertFileExists(sprintf('%s/vendor', $context->getReferenceExecutionDirectory()));
         //check for non existence of lock file, composer generates this when updating if it doesn't exist
@@ -84,7 +84,7 @@ public function testIfSolutionRequiresComposerComposerInstallIsExecuted(): void
         $exercise->setSolution($solution);
 
         $event = new ExerciseRunnerEvent('event', $context);
-        (new PrepareSolutionListener(new HostProcessFactory()))->__invoke($event);
+        (new PrepareSolutionListener(new HostSandbox()))->__invoke($event);
 
         $this->assertFileExists(sprintf('%s/vendor', $context->getReferenceExecutionDirectory()));
     }
@@ -119,7 +119,7 @@ public function testExceptionIsThrownIfDependenciesCannotBeResolved(): void
             ->willReturn(true);
 
         $event = new ExerciseRunnerEvent('event', $context);
-        (new PrepareSolutionListener(new HostProcessFactory()))->__invoke($event);
+        (new PrepareSolutionListener(new HostSandbox()))->__invoke($event);
 
         $this->assertFileExists(sprintf('%s/vendor', $context->getReferenceExecutionDirectory()));
     }
diff --git a/test/Process/DockerExecutionTest.php b/test/Process/DockerExecutionTest.php
new file mode 100644
index 00000000..88444e1b
--- /dev/null
+++ b/test/Process/DockerExecutionTest.php
@@ -0,0 +1,47 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpSchool\PhpWorkshopTest\Process;
+
+use PhpSchool\PhpWorkshop\Process\DockerExecution;
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Process\Process;
+
+class DockerExecutionTest extends TestCase
+{
+    public function testStepsRunAroundTheMainProcess(): void
+    {
+        $log = tempnam(sys_get_temp_dir(), 'steps');
+
+        $execution = new DockerExecution(
+            Process::fromShellCommandline('echo main >> ' . $log),
+            [Process::fromShellCommandline('echo before >> ' . $log)],
+            [Process::fromShellCommandline('echo after >> ' . $log)],
+        );
+
+        $execution->start();
+        $execution->wait();
+
+        $this->assertSame("before\nmain\nafter\n", file_get_contents($log));
+        unlink($log);
+    }
+
+    public function testAfterStepsRunWhenTheMainProcessFails(): void
+    {
+        $log = tempnam(sys_get_temp_dir(), 'steps');
+
+        $execution = new DockerExecution(
+            Process::fromShellCommandline('exit 1'),
+            [],
+            [Process::fromShellCommandline('echo after >> ' . $log)],
+        );
+
+        $execution->start();
+        $execution->wait();
+
+        $this->assertFalse($execution->isSuccessful());
+        $this->assertSame("after\n", file_get_contents($log));
+        unlink($log);
+    }
+}
diff --git a/test/Process/DockerProcessFactoryTest.php b/test/Process/DockerSandboxTest.php
similarity index 88%
rename from test/Process/DockerProcessFactoryTest.php
rename to test/Process/DockerSandboxTest.php
index e3e7fd5a..85e53515 100644
--- a/test/Process/DockerProcessFactoryTest.php
+++ b/test/Process/DockerSandboxTest.php
@@ -2,15 +2,15 @@
 
 namespace PhpSchool\PhpWorkshopTest\Process;
 
-use PhpSchool\PhpWorkshop\Process\DockerProcessFactory;
+use PhpSchool\PhpWorkshop\Process\DockerSandbox;
 use PhpSchool\PhpWorkshop\Process\ProcessInput;
 use PhpSchool\PhpWorkshop\Process\ProcessNotFoundException;
 use PHPUnit\Framework\TestCase;
 use Symfony\Component\Process\ExecutableFinder;
 
-class DockerProcessFactoryTest extends TestCase
+class DockerSandboxTest extends TestCase
 {
-    private function factory(string $portsNetwork = 'bridge'): DockerProcessFactory
+    private function factory(string $portsNetwork = 'bridge'): DockerSandbox
     {
         $finder = $this->createMock(ExecutableFinder::class);
         $finder->expects($this->once())
@@ -18,7 +18,7 @@ private function factory(string $portsNetwork = 'bridge'): DockerProcessFactory
             ->with('docker')
             ->willReturn('/usr/local/bin/docker');
 
-        return new DockerProcessFactory('/docker-dir', 'PHP8Appreciate', '/composer/cache/dir', $finder, $portsNetwork);
+        return new DockerSandbox('/docker-dir', 'PHP8Appreciate', '/composer/cache/dir', $finder, $portsNetwork);
     }
 
     /**
@@ -52,7 +52,7 @@ public function testCreateThrowsExceptionIfDockerNotFound(): void
             ->with('docker')
             ->willReturn(null);
 
-        $factory = new DockerProcessFactory('/docker-dir', 'php8appreciate', '/composer/cache/dir', $finder);
+        $factory = new DockerSandbox('/docker-dir', 'php8appreciate', '/composer/cache/dir', $finder);
         $input = new ProcessInput('composer', [], __DIR__, [], []);
 
         $factory->create($input);
@@ -60,7 +60,7 @@ public function testCreateThrowsExceptionIfDockerNotFound(): void
 
     public function testCreateIsIsolatedWithNoNetwork(): void
     {
-        $process = $this->factory()->create(new ProcessInput('php', ['one', 'two'], __DIR__, [], []));
+        $process = $this->factory()->create(new ProcessInput('php', ['one', 'two'], __DIR__, [], []))->process;
 
         $expected = $this->expectedCommand(
             ['--network', 'none'],
@@ -74,7 +74,7 @@ public function testCreateIsIsolatedWithNoNetwork(): void
 
     public function testComposerGetsNetworkCacheAndNoPluginsOrScripts(): void
     {
-        $process = $this->factory()->create(new ProcessInput('composer', ['install'], __DIR__, [], []));
+        $process = $this->factory()->create(new ProcessInput('composer', ['install'], __DIR__, [], []))->process;
 
         $expected = $this->expectedCommand(
             ['--network', 'bridge'],
@@ -86,7 +86,7 @@ public function testComposerGetsNetworkCacheAndNoPluginsOrScripts(): void
 
     public function testExposedPortsArePublishedOnLoopbackOnly(): void
     {
-        $process = $this->factory()->create(new ProcessInput('php', [], __DIR__, [], [8000]));
+        $process = $this->factory()->create(new ProcessInput('php', [], __DIR__, [], [8000]))->process;
 
         $expected = $this->expectedCommand(
             ['--network', 'bridge', '-p', '127.0.0.1:8000:8000'],
@@ -98,7 +98,7 @@ public function testExposedPortsArePublishedOnLoopbackOnly(): void
 
     public function testExposedPortsUseTheGivenNetwork(): void
     {
-        $process = $this->factory('php-school-sandbox')->create(new ProcessInput('php', [], __DIR__, [], [8000]));
+        $process = $this->factory('php-school-sandbox')->create(new ProcessInput('php', [], __DIR__, [], [8000]))->process;
 
         $expected = $this->expectedCommand(
             ['--network', 'php-school-sandbox', '-p', '127.0.0.1:8000:8000'],
@@ -110,7 +110,7 @@ public function testExposedPortsUseTheGivenNetwork(): void
 
     public function testCreateWithEnv(): void
     {
-        $process = $this->factory()->create(new ProcessInput('php', [], __DIR__, ['SOME_VAR' => 'value'], []));
+        $process = $this->factory()->create(new ProcessInput('php', [], __DIR__, ['SOME_VAR' => 'value'], []))->process;
 
         $expected = $this->expectedCommand(
             ['--network', 'none'],
@@ -122,7 +122,7 @@ public function testCreateWithEnv(): void
 
     public function testWithInput(): void
     {
-        $process = $this->factory()->create(new ProcessInput('php', [], __DIR__, [], [], 'someinput'));
+        $process = $this->factory()->create(new ProcessInput('php', [], __DIR__, [], [], 'someinput'))->process;
 
         static::assertSame('someinput', $process->getInput());
     }
diff --git a/test/Process/HostProcessFactoryTest.php b/test/Process/HostSandboxTest.php
similarity index 82%
rename from test/Process/HostProcessFactoryTest.php
rename to test/Process/HostSandboxTest.php
index 8e334f82..191ec899 100644
--- a/test/Process/HostProcessFactoryTest.php
+++ b/test/Process/HostSandboxTest.php
@@ -5,10 +5,10 @@
 use PhpSchool\PhpWorkshop\Process\ProcessInput;
 use PhpSchool\PhpWorkshop\Process\ProcessNotFoundException;
 use Symfony\Component\Process\ExecutableFinder;
-use PhpSchool\PhpWorkshop\Process\HostProcessFactory;
+use PhpSchool\PhpWorkshop\Process\HostSandbox;
 use PHPUnit\Framework\TestCase;
 
-class HostProcessFactoryTest extends TestCase
+class HostSandboxTest extends TestCase
 {
     public function testCreateThrowsExceptionIfExecutableNotFound(): void
     {
@@ -20,7 +20,7 @@ public function testCreateThrowsExceptionIfExecutableNotFound(): void
             ->with('composer')
             ->willReturn(null);
 
-        $factory = new HostProcessFactory($finder);
+        $factory = new HostSandbox($finder);
         $input = new ProcessInput('composer', [], __DIR__, [], []);
 
         $factory->create($input);
@@ -34,10 +34,10 @@ public function testCreate(): void
             ->with('composer')
             ->willReturn('/usr/local/bin/composer');
 
-        $factory = new HostProcessFactory($finder);
+        $factory = new HostSandbox($finder);
         $input = new ProcessInput('composer', [], __DIR__, [], []);
 
-        $process = $factory->create($input);
+        $process = $factory->create($input)->process;
         static::assertSame("'/usr/local/bin/composer'", $process->getCommandLine());
     }
 
@@ -49,10 +49,10 @@ public function testCreateWithArgs(): void
             ->with('composer')
             ->willReturn('/usr/local/bin/composer');
 
-        $factory = new HostProcessFactory($finder);
+        $factory = new HostSandbox($finder);
         $input = new ProcessInput('composer', ['one', 'two'], __DIR__, [], []);
 
-        $process = $factory->create($input);
+        $process = $factory->create($input)->process;
         static::assertSame("'/usr/local/bin/composer' 'one' 'two'", $process->getCommandLine());
     }
 
@@ -64,10 +64,10 @@ public function testCreateWithEnv(): void
             ->with('composer')
             ->willReturn('/usr/local/bin/composer');
 
-        $factory = new HostProcessFactory($finder);
+        $factory = new HostSandbox($finder);
         $input = new ProcessInput('composer', ['one', 'two'], __DIR__, ['SOME_VAR' => 'value'], []);
 
-        $process = $factory->create($input);
+        $process = $factory->create($input)->process;
         static::assertSame('value', $process->getEnv()['SOME_VAR']);
     }
 
@@ -76,7 +76,7 @@ public function testInheritedEnvIsRemovedExceptAllowed(): void
         putenv('PHPSCHOOL_SECRET=secret');
 
         try {
-            $process = (new HostProcessFactory())->create(
+            $process = (new HostSandbox())->create(
                 new ProcessInput('php', ['-r', 'echo json_encode([getenv("PHPSCHOOL_SECRET"), getenv("PATH") !== false]);'], __DIR__, [], []),
             );
             $process->mustRun();
@@ -95,10 +95,10 @@ public function testWithInput(): void
             ->with('composer')
             ->willReturn('/usr/local/bin/composer');
 
-        $factory = new HostProcessFactory($finder);
+        $factory = new HostSandbox($finder);
         $input = new ProcessInput('composer', [], __DIR__, [], [], 'someinput');
 
-        $process = $factory->create($input);
+        $process = $factory->create($input)->process;
         static::assertSame('someinput', $process->getInput());
     }
 }