diff --git a/composer.json b/composer.json
index e808466..4218ad0 100644
--- a/composer.json
+++ b/composer.json
@@ -28,7 +28,7 @@
   },
   "extra": {
     "class": "Seacms\\ComposerInstaller\\Plugin",
-    "plugin-modifies-downloads": true,
-    "plugin-modifies-install-path": true
+    "plugin-modifies-downloads": false,
+    "plugin-modifies-install-path": false
   }
 }
diff --git a/src/NotFoundFileException.php b/src/NotFoundFileException.php
new file mode 100644
index 0000000..cfdebda
--- /dev/null
+++ b/src/NotFoundFileException.php
@@ -0,0 +1,17 @@
+<?php
+
+/**
+ * SPDX-License-Identifier: EUPL-1.2
+ * Authors: see /README.md
+ */
+
+namespace Seacms\ComposerInstaller;
+
+use Exception;
+
+/**
+ * Exception when file not found
+ */
+
+class NotFoundFileException extends Exception
+{}
\ No newline at end of file
diff --git a/src/Plugin.php b/src/Plugin.php
index 3ebd86c..6662ac6 100644
--- a/src/Plugin.php
+++ b/src/Plugin.php
@@ -8,15 +8,46 @@
 namespace Seacms\ComposerInstaller;
 
 use Composer\Composer;
+use Composer\Config;
+use Composer\EventDispatcher\EventSubscriberInterface;
+use Composer\Installer\PackageEvent;
+use Composer\Installer\PackageEvents;
+use Composer\Json\JsonFile;
 use Composer\IO\IOInterface;
 use Composer\Plugin\PluginInterface;
+use Seacms\ComposerInstaller\NotFoundFileException;
 
 /**
  * Composer plugin to install or not packages from local path
  */
 
-class Plugin implements PluginInterface
+class Plugin implements PluginInterface, EventSubscriberInterface
 {
+    /**
+     * composer instance
+     * @var Composer
+     */
+    protected $composer;
+    /**
+     * io instance
+     * @var IOInterface
+     */
+    protected $io;
+    
+    /**
+     * Returns an array of event names this subscriber wants to listen to.
+     * @return array<string, string|array{0: string, 1?: int}|array<array{0: string, 1?: int}>> The event names to listen to
+     */
+    public static function getSubscribedEvents(){
+        return [
+            PackageEvents::PRE_PACKAGE_UPDATE => 'prePackageUpdate',
+        ];
+    } 
+    
+    public function prePackageUpdate(PackageEvent $event)
+    {
+        $event->getIO()->write("<info>Test : {$event->getOperation()}</info>");
+    }
     
     /**
      * Apply plugin modifications to Composer
@@ -24,7 +55,13 @@ class Plugin implements PluginInterface
      * @return void
      */
     public function activate(Composer $composer, IOInterface $io){
-
+        $this->composer = $composer;
+        $this->io = $io;
+        try {
+            $this->updateConfig($this->getConfigJsonFile());
+        } catch (NotFoundFileException $ex){
+            // do nothing
+        }
     }
 
     /**
@@ -50,4 +87,100 @@ class Plugin implements PluginInterface
     public function uninstall(Composer $composer, IOInterface $io){
         
     }
+    
+    /**
+     * get config.json File from root path
+     * @return array ['config' => $config,'path'=>path]
+     * @throws NotFoundFileException
+     */
+    protected function getConfigJsonFile(): array
+    {
+        $file = new JsonFile('./main-config.json');
+        if (!$file->exists()){
+            throw new NotFoundFileException("main-config.json file not existing");
+        }
+        $config = $file->read();
+        if (!is_array($config)){
+            $this->io->write('<error>Error loading main-config.json : it should contain an array</error>');
+            throw new NotFoundFileException("main-config.json file not existing");
+        }
+        return ['config'=>$config,'path'=>$file->getPath()];
+    }
+    
+    /**
+     * update config with configFile
+     * @param array $config
+     */
+    protected function updateConfig(array $config)
+    {
+        if (isset($config['config']['local-repositories']) && is_array($config['config']['local-repositories'])){
+            $composerConfig = $this->composer->getConfig();
+            foreach($config['config']['local-repositories'] as $name => $packageName){
+                if (is_string($name) && !empty(basename($name)) 
+                    && is_string($packageName) && !empty($packageName) && !in_array(basename($name),['.','..'])){
+                    $projectName = basename($name);
+                    $dirName = "../$projectName";
+                    if (is_dir($dirName)){
+                        $this->io->write("<info>Using local path for '$projectName'</info>");
+                        // $previousRepositories = $composerConfig->all()['repositories'];
+                        // $this->io->write("<info>previous : ".json_encode($previousRepositories)."</info>");
+                        // $newRepositories = $this->replaceFromConfigWithPath($composerConfig,$projectName,$packageName);
+                        // $this->io->write("<info>new : ".json_encode($newRepositories)."</info>");
+                        $composerConfig->merge([
+                            'repositories' => [
+                                $packageName => [
+                                    'type' => 'path',
+                                    'url' => "../$projectName",
+                                    'options' => [
+                                        'name' => $packageName,
+                                        'versions' => [
+                                            $packageName => 'dev-master',
+                                            'symlink' => true
+                                        ]
+                                    ]
+                                ]
+                            ]
+                        ]);
+                        $previousRepositories = $composerConfig->all()['repositories'];
+                        $this->io->write("<info>previous : ".json_encode($previousRepositories)."</info>");
+                    }
+                }
+            }
+        }
+    }
+    
+    /**
+     * replace from config repositories vcs by path
+     * @param Config $composerConfig
+     * @param string $projectName
+     * @param string $packageName
+     * @return array $newRepositories
+     */
+    protected function replaceFromConfigWithPath(
+        Config $composerConfig, 
+        string $projectName, 
+        string $packageName): array
+    {
+        $repositories = $composerConfig->all()['repositories'];
+        foreach($repositories as $idx => $data){
+            if (is_array($data) && isset($data['type']) && $data['type'] === 'vcs' && 
+                isset($data['url']) && is_string($data['url']) &&
+                substr($data['url'],0,-strlen($projectName)) == 'https://git.defis.info/SeaCMS/' &&
+                substr($data['url'],-strlen($projectName)) == $projectName
+                ){
+                $repositories[$idx] = [
+                    'type' => 'path',
+                    'url' => "../$projectName",
+                    'options' => [
+                        'name' => $packageName,
+                        'versions' => [
+                            $packageName => 'dev-master',
+                            'symlink' => true
+                        ]
+                    ]
+                ];
+            }
+        }
+        return $repositories;
+    }
 }
\ No newline at end of file