diff --git a/src/Composer/Command/ReinstallCommand.php b/src/Composer/Command/ReinstallCommand.php
index 3143fc50c32a..76e2f0294647 100644
--- a/src/Composer/Command/ReinstallCommand.php
+++ b/src/Composer/Command/ReinstallCommand.php
@@ -21,6 +21,8 @@
 use Composer\Pcre\Preg;
 use Composer\Plugin\CommandEvent;
 use Composer\Plugin\PluginEvents;
+use Composer\Script\ScriptEvents;
+use Composer\Util\Platform;
 use Symfony\Component\Console\Input\InputInterface;
 use Symfony\Component\Console\Input\InputOption;
 use Symfony\Component\Console\Input\InputArgument;
@@ -146,8 +148,13 @@ protected function execute(InputInterface $input, OutputInterface $output)
         $downloadManager->setPreferSource($preferSource);
         $downloadManager->setPreferDist($preferDist);
 
-        $installationManager->execute($localRepo, $uninstallOperations, true);
-        $installationManager->execute($localRepo, $installOperations, true);
+        $devMode = $localRepo->getDevMode() !== null ? $localRepo->getDevMode() : true;
+
+        Platform::putEnv('COMPOSER_DEV_MODE', $devMode ? '1' : '0');
+        $composer->getEventDispatcher()->dispatchScript(ScriptEvents::PRE_INSTALL_CMD, $devMode);
+
+        $installationManager->execute($localRepo, $uninstallOperations, $devMode);
+        $installationManager->execute($localRepo, $installOperations, $devMode);
 
         if (!$input->getOption('no-autoloader')) {
             $optimize = $input->getOption('optimize-autoloader') || $config->get('optimize-autoloader');
@@ -162,6 +169,8 @@ protected function execute(InputInterface $input, OutputInterface $output)
             $generator->dump($config, $localRepo, $package, $installationManager, 'composer', $optimize);
         }
 
+        $composer->getEventDispatcher()->dispatchScript(ScriptEvents::POST_INSTALL_CMD, $devMode);
+
         return 0;
     }
 }
diff --git a/src/Composer/Repository/FilesystemRepository.php b/src/Composer/Repository/FilesystemRepository.php
index 6f130ce05393..781a79d0f14e 100644
--- a/src/Composer/Repository/FilesystemRepository.php
+++ b/src/Composer/Repository/FilesystemRepository.php
@@ -36,6 +36,8 @@ class FilesystemRepository extends WritableArrayRepository
     private $rootPackage;
     /** @var Filesystem */
     private $filesystem;
+    /** @var bool|null */
+    private $devMode = null;
 
     /**
      * Initializes filesystem repository.
@@ -56,6 +58,14 @@ public function __construct(JsonFile $repositoryFile, $dumpVersions = false, Roo
         }
     }
 
+    /**
+     * @inheritDoc
+     */
+    public function getDevMode()
+    {
+        return $this->devMode;
+    }
+
     /**
      * Initializes repository (reads file, or remote address).
      */
@@ -78,6 +88,9 @@ protected function initialize()
             if (isset($data['dev-package-names'])) {
                 $this->setDevPackageNames($data['dev-package-names']);
             }
+            if (isset($data['dev'])) {
+                $this->devMode = $data['dev'];
+            }
 
             if (!is_array($packages)) {
                 throw new \UnexpectedValueException('Could not parse package list from the repository');
diff --git a/src/Composer/Repository/InstalledRepositoryInterface.php b/src/Composer/Repository/InstalledRepositoryInterface.php
index b5d8a264e39a..a25d7369e2e7 100644
--- a/src/Composer/Repository/InstalledRepositoryInterface.php
+++ b/src/Composer/Repository/InstalledRepositoryInterface.php
@@ -21,6 +21,11 @@
  */
 interface InstalledRepositoryInterface extends WritableRepositoryInterface
 {
+    /**
+     * @return bool|null true if dev requirements were installed, false if --no-dev was used, null if yet unknown
+     */
+    public function getDevMode();
+
     /**
      * @return bool true if packages were never installed in this repository
      */
diff --git a/src/Composer/Repository/WritableArrayRepository.php b/src/Composer/Repository/WritableArrayRepository.php
index 2cf2f576acc2..1ca2bd636a6b 100644
--- a/src/Composer/Repository/WritableArrayRepository.php
+++ b/src/Composer/Repository/WritableArrayRepository.php
@@ -27,6 +27,17 @@ class WritableArrayRepository extends ArrayRepository implements WritableReposit
      */
     protected $devPackageNames = array();
 
+    /** @var bool|null */
+    private $devMode = null;
+
+    /**
+     * @inheritDoc
+     */
+    public function getDevMode()
+    {
+        return $this->devMode;
+    }
+
     /**
      * @inheritDoc
      */
@@ -48,6 +59,7 @@ public function getDevPackageNames()
      */
     public function write($devMode, InstallationManager $installationManager)
     {
+        $this->devMode = $devMode;
     }
 
     /**
@@ -55,6 +67,7 @@ public function write($devMode, InstallationManager $installationManager)
      */
     public function reload()
     {
+        $this->devMode = null;
     }
 
     /**