diff --git a/src/Composer/Command/CreateProjectCommand.php b/src/Composer/Command/CreateProjectCommand.php
index 5c0039b77..a859ac12a 100644
--- a/src/Composer/Command/CreateProjectCommand.php
+++ b/src/Composer/Command/CreateProjectCommand.php
@@ -120,7 +120,9 @@ EOT
         $composer = Factory::create($io);
         $installer = Installer::create($io, $composer);
 
-        $installer->run($preferSource);
+        $installer
+            ->setPreferSource($preferSource)
+            ->run();
     }
 
     protected function createDownloadManager(IOInterface $io)
diff --git a/src/Composer/Command/InstallCommand.php b/src/Composer/Command/InstallCommand.php
index d06278e7d..7bf90709e 100644
--- a/src/Composer/Command/InstallCommand.php
+++ b/src/Composer/Command/InstallCommand.php
@@ -53,12 +53,14 @@ EOT
         $io = $this->getApplication()->getIO();
         $install = Installer::create($io, $composer);
 
-        return $install->run(
-            (Boolean) $input->getOption('prefer-source'),
-            (Boolean) $input->getOption('dry-run'),
-            (Boolean) $input->getOption('verbose'),
-            (Boolean) $input->getOption('no-install-recommends'),
-            (Boolean) $input->getOption('install-suggests')
-        );
+        $install
+            ->setDryRun($input->getOption('dry-run'))
+            ->setVerbose($input->getOption('verbose'))
+            ->setPreferSource($input->getOption('prefer-source'))
+            ->setInstallRecommends(!$input->getOption('no-install-recommends'))
+            ->setInstallSuggests($input->getOption('install-suggests'))
+        ;
+
+        return $install->run();
     }
 }
diff --git a/src/Composer/Command/UpdateCommand.php b/src/Composer/Command/UpdateCommand.php
index cc0960504..7fe888139 100644
--- a/src/Composer/Command/UpdateCommand.php
+++ b/src/Composer/Command/UpdateCommand.php
@@ -51,13 +51,15 @@ EOT
         $io = $this->getApplication()->getIO();
         $install = Installer::create($io, $composer);
 
-        return $install->run(
-            (Boolean)$input->getOption('prefer-source'),
-            (Boolean)$input->getOption('dry-run'),
-            (Boolean)$input->getOption('verbose'),
-            (Boolean)$input->getOption('no-install-recommends'),
-            (Boolean)$input->getOption('install-suggests'),
-            true
-        );
+        $install
+            ->setDryRun($input->getOption('dry-run'))
+            ->setVerbose($input->getOption('verbose'))
+            ->setPreferSource($input->getOption('prefer-source'))
+            ->setInstallRecommends(!$input->getOption('no-install-recommends'))
+            ->setInstallSuggests($input->getOption('install-suggests'))
+            ->setUpdate(true)
+        ;
+
+        return $install->run();
     }
 }
diff --git a/src/Composer/Installer.php b/src/Composer/Installer.php
index f6fb70c1d..a0f85576a 100644
--- a/src/Composer/Installer.php
+++ b/src/Composer/Installer.php
@@ -75,6 +75,18 @@ class Installer
      */
     protected $eventDispatcher;
 
+    protected $preferSource = false;
+    protected $dryRun = false;
+    protected $verbose = false;
+    protected $installRecommends = true;
+    protected $installSuggests = false;
+    protected $update = false;
+
+    /**
+     * @var RepositoryInterface
+     */
+    protected $additionalInstalledRepository;
+
     /**
      * Constructor
      *
@@ -99,37 +111,27 @@ class Installer
 
     /**
      * Run installation (or update)
-     *
-     * @param Boolean $preferSource
-     * @param Boolean $dryRun
-     * @param Boolean $verbose
-     * @param Boolean $noInstallRecommends
-     * @param Boolean $installSuggests
-     * @param Boolean $update
-     * @param RepositoryInterface $additionalInstalledRepository
      */
-    public function run($preferSource = false, $dryRun = false, $verbose = false, $noInstallRecommends = false, $installSuggests = false, $update = false, RepositoryInterface $additionalInstalledRepository = null)
+    public function run()
     {
-        if ($dryRun) {
-            $verbose = true;
+        if ($this->dryRun) {
+            $this->verbose = true;
         }
 
-        if ($preferSource) {
+        if ($this->preferSource) {
             $this->downloadManager->setPreferSource(true);
         }
 
-        $this->repositoryManager = $this->repositoryManager;
-
         // create local repo, this contains all packages that are installed in the local project
         $localRepo = $this->repositoryManager->getLocalRepository();
         // create installed repo, this contains all local packages + platform packages (php & extensions)
         $installedRepo = new CompositeRepository(array($localRepo, new PlatformRepository()));
-        if ($additionalInstalledRepository) {
-            $installedRepo->addRepository($additionalInstalledRepository);
+        if ($this->additionalInstalledRepository) {
+            $installedRepo->addRepository($this->additionalInstalledRepository);
         }
 
         // prepare aliased packages
-        if (!$update && $this->locker->isLocked()) {
+        if (!$this->update && $this->locker->isLocked()) {
             $aliases = $this->locker->getAliases();
         } else {
             $aliases = $this->package->getAliases();
@@ -152,20 +154,20 @@ class Installer
         }
 
         // dispatch pre event
-        if (!$dryRun) {
-            $eventName = $update ? ScriptEvents::PRE_UPDATE_CMD : ScriptEvents::PRE_INSTALL_CMD;
+        if (!$this->dryRun) {
+            $eventName = $this->update ? ScriptEvents::PRE_UPDATE_CMD : ScriptEvents::PRE_INSTALL_CMD;
             $this->eventDispatcher->dispatchCommandEvent($eventName);
         }
 
         // creating requirements request
         $installFromLock = false;
         $request = new Request($pool);
-        if ($update) {
+        if ($this->update) {
             $this->io->write('<info>Updating dependencies</info>');
 
             $request->updateAll();
 
-            $links = $this->collectLinks($noInstallRecommends, $installSuggests);
+            $links = $this->collectLinks();
 
             foreach ($links as $link) {
                 $request->install($link->getTarget(), $link->getConstraint());
@@ -192,7 +194,7 @@ class Installer
         } else {
             $this->io->write('<info>Installing dependencies</info>');
 
-            $links = $this->collectLinks($noInstallRecommends, $installSuggests);
+            $links = $this->collectLinks();
 
             foreach ($links as $link) {
                 $request->install($link->getTarget(), $link->getConstraint());
@@ -207,7 +209,7 @@ class Installer
         $operations = $solver->solve($request);
 
         // force dev packages to be updated to latest reference on update
-        if ($update) {
+        if ($this->update) {
             foreach ($localRepo->getPackages() as $package) {
                 if ($package instanceof AliasPackage) {
                     $package = $package->getAliasOf();
@@ -249,10 +251,10 @@ class Installer
         }
 
         foreach ($operations as $operation) {
-            if ($verbose) {
+            if ($this->verbose) {
                 $this->io->write((string) $operation);
             }
-            if (!$dryRun) {
+            if (!$this->dryRun) {
                 $this->eventDispatcher->dispatchPackageEvent(constant('Composer\Script\ScriptEvents::PRE_PACKAGE_'.strtoupper($operation->getJobType())), $operation);
 
                 // if installing from lock, restore dev packages' references to their locked state
@@ -279,8 +281,8 @@ class Installer
             }
         }
 
-        if (!$dryRun) {
-            if ($update || !$this->locker->isLocked()) {
+        if (!$this->dryRun) {
+            if ($this->update || !$this->locker->isLocked()) {
                 $this->locker->setLockData($localRepo->getPackages(), $aliases);
                 $this->io->write('<info>Writing lock file</info>');
             }
@@ -292,20 +294,20 @@ class Installer
             $generator->dump($localRepo, $this->package, $this->installationManager, $this->installationManager->getVendorPath().'/.composer');
 
             // dispatch post event
-            $eventName = $update ? ScriptEvents::POST_UPDATE_CMD : ScriptEvents::POST_INSTALL_CMD;
+            $eventName = $this->update ? ScriptEvents::POST_UPDATE_CMD : ScriptEvents::POST_INSTALL_CMD;
             $this->eventDispatcher->dispatchCommandEvent($eventName);
         }
     }
 
-    private function collectLinks($noInstallRecommends, $installSuggests)
+    private function collectLinks()
     {
         $links = $this->package->getRequires();
 
-        if (!$noInstallRecommends) {
+        if ($this->installRecommends) {
             $links = array_merge($links, $this->package->getRecommends());
         }
 
-        if ($installSuggests) {
+        if ($this->installSuggests) {
             $links = array_merge($links, $this->package->getSuggests());
         }
 
@@ -334,4 +336,89 @@ class Installer
             $eventDispatcher
         );
     }
+
+    public function setAdditionalInstalledRepository(RepositoryInterface $additionalInstalledRepository)
+    {
+        $this->additionalInstalledRepository = $additionalInstalledRepository;
+
+        return $this;
+    }
+
+    /**
+     * wether to run in drymode or not
+     *
+     * @param boolean $dryRun
+     * @return Installer
+     */
+    public function setDryRun($dryRun=true)
+    {
+        $this->dryRun = (boolean) $dryRun;
+
+        return $this;
+    }
+
+    /**
+     * install recommend packages
+     *
+     * @param boolean $noInstallRecommends
+     * @return Installer
+     */
+    public function setInstallRecommends($installRecommends=true)
+    {
+        $this->installRecommends = (boolean) $installRecommends;
+
+        return $this;
+    }
+
+    /**
+     * also install suggested packages
+     *
+     * @param boolean $installSuggests
+     * @return Installer
+     */
+    public function setInstallSuggests($installSuggests=true)
+    {
+        $this->installSuggests = (boolean) $installSuggests;
+
+        return $this;
+    }
+
+    /**
+     * prefer source installation
+     *
+     * @param boolean $preferSource
+     * @return Installer
+     */
+    public function setPreferSource($preferSource=true)
+    {
+        $this->preferSource = (boolean) $preferSource;
+
+        return $this;
+    }
+
+    /**
+     * update packages
+     *
+     * @param boolean $update
+     * @return Installer
+     */
+    public function setUpdate($update=true)
+    {
+        $this->update = (boolean) $update;
+
+        return $this;
+    }
+
+    /**
+     * run in verbose mode
+     *
+     * @param boolean $verbose
+     * @return Installer
+     */
+    public function setVerbose($verbose=true)
+    {
+        $this->verbose = (boolean) $verbose;
+
+        return $this;
+    }
 }