diff --git a/src/Composer/Storage/ArchiveStorage.php b/src/Composer/Storage/ArchiveStorage.php
index 30c447ed2db7..2e5df29c1b55 100644
--- a/src/Composer/Storage/ArchiveStorage.php
+++ b/src/Composer/Storage/ArchiveStorage.php
@@ -75,12 +75,12 @@ public function storePackage(PackageInterface $package, $sourceDir)
             throw new \RuntimeException('Can not initialize directory structure in ' . $dir);
         }
 
-        if (file_exists($fileName)) {
-            @unlink($fileName);
+        $tempFileName = sys_get_temp_dir().'/'.uniqid(basename($fileName));
+        $this->compressor->compressDir($sourceDir, $tempFileName);
+        if (!@rename($tempFileName, $fileName)) {
+            throw new \RuntimeException(sprintf('Can not rename file from %s to %s.', $tempFileName, $fileName));
         }
 
-        $this->compressor->compressDir($sourceDir, $fileName);
-
         return $this->createDistribution($fileName);
     }
 
diff --git a/src/Composer/Storage/RepositoryStorage.php b/src/Composer/Storage/RepositoryStorage.php
index 798a26309dae..8034ff2ea964 100644
--- a/src/Composer/Storage/RepositoryStorage.php
+++ b/src/Composer/Storage/RepositoryStorage.php
@@ -71,6 +71,10 @@ public function storePackage(PackageInterface $package, $sourceDir)
 
         $packageCopy = self::convertPackage($package, $dist);
 
+        // Remove old package from repository in a replace situation
+        if ($this->repository->hasPackage($package)) {
+            $this->repository->removePackage($package);
+        }
         $this->repository->addPackage($packageCopy);
         $this->repository->write();