diff --git a/src/Gist/Composer/PostInstallHandler.php b/src/Gist/Composer/PostInstallHandler.php
new file mode 100644
index 0000000..81650a0
--- /dev/null
+++ b/src/Gist/Composer/PostInstallHandler.php
@@ -0,0 +1,211 @@
+<?php
+
+namespace Gist\Composer;
+
+use Symfony\Component\Process\PhpExecutableFinder;
+use Symfony\Component\Process\Process;
+use Composer\Script\Event;
+use Symfony\Component\Console\Helper\QuestionHelper;
+use Symfony\Component\Console\Question\ConfirmationQuestion;
+use Symfony\Component\Console\Input\ArgvInput;
+use Symfony\Component\Console\Output\ConsoleOutput;
+use Symfony\Component\Filesystem\Filesystem;
+use Symfony\Component\Console\Question\ChoiceQuestion;
+use Symfony\Component\Console\Question\Question;
+use Symfony\Component\Yaml\Yaml;
+
+/**
+ * class PostInstallHandler.
+ *
+ * @author Simon Vieille <simon@deblan.fr>
+ */
+class PostInstallHandler
+{
+    public static function execute(Event $event)
+    {
+        $helper = new QuestionHelper();
+        $input = new ArgvInput();
+        $output = new ConsoleOutput();
+        $filesystem = new Filesystem();
+
+        $output->writeln('+==============================+');
+        $output->writeln('| GIST Setup                   |');
+        $output->writeln('+==============================+');
+        $output->writeln('');
+        $output->writeln('1. Database');
+        $output->writeln('===========');
+
+        $configure = true;
+        if ($filesystem->exists('propel.yaml')) {
+            $output->writeln('The configuration file exists.');
+            $question = new ConfirmationQuestion('Your current configuration will not be merged. Do you want to override it? [y/N] ', false);
+            $configure = $helper->ask($input, $output, $question);
+        } else {
+            $configure = true;
+        }
+
+        if ($configure) {
+            $choices = ['MySQL/MariaDB', 'SQLite', 'other'];
+            $question = new ChoiceQuestion('Which DBMS? ', $choices, 0);
+            $dbms = $helper->ask($input, $output, $question);
+            $substitutions = [];
+
+            if ($dbms === 'MySQL/MariaDB') {
+                $templateName = 'propel.yaml.dist-mysql';
+
+                $question = new Question('Host: [127.0.0.1] ', '127.0.0.1');
+                $substitutions['DATABASE_HOST'] = $helper->ask($input, $output, $question);
+
+                $question = new Question('Database (it must exists!): [gist] ', 'gist');
+                $substitutions['DATABASE_NAME'] = $helper->ask($input, $output, $question);
+
+                $question = new Question('Username: [root] ', 'root');
+                $substitutions['DATABASE_USERNAME'] = $helper->ask($input, $output, $question);
+
+                $question = new Question('Password: [] ', '');
+                $substitutions['DATABASE_PASSWORD'] = $helper->ask($input, $output, $question);
+            } elseif ($dbms === 'SQLite') {
+                $defaultPath = getcwd().'/app/data/gist.sqlite';
+                $question = new Question("Ok! Where do you want me to save datas? [$defaultPath] ", $defaultPath);
+                $substitutions['DATABASE_PATH'] = $helper->ask($input, $output, $question);
+                $templateName = 'propel.yaml.dist-sqlite';
+            } else {
+                $output->writeln('See README.md to perform the configuration.');
+
+                return;
+            }
+
+            $template = file_get_contents('app/config/'.$templateName);
+            $content = str_replace(
+                array_keys($substitutions),
+                array_values($substitutions),
+                $template
+            );
+
+            $done = file_put_contents('propel.yaml', $content) !== false;
+
+            if ($done) {
+                $output->writeln('Running migration...');
+
+                foreach (['config:convert', 'model:build --recursive', 'migration:diff --recursive', 'migration:migrate --recursive'] as $arg) {
+                    $command = self::getPhp(true).' ./vendor/propel/propel/bin/propel '.$arg;
+                    $process = new Process($command);
+                    $process->run();
+
+                    if (!$process->isSuccessful()) {
+                        $output->writeln('An error occured while executing:');
+                        $output->writeln($command);
+                        $output->writeln('To perform the configuration. See README.md.');
+
+                        return;
+                    }
+                }
+
+                $output->writeln('Done!');
+            } else {
+                $output->writeln('An error occured. See README.md to perform the configuration.');
+            }
+        }
+
+        $output->writeln('');
+        $output->writeln('2. Application');
+        $output->writeln('==============');
+
+        $configure = true;
+        if ($filesystem->exists('app/config/config.yml')) {
+            $output->writeln('The configuration file exists.');
+            $question = new ConfirmationQuestion('Your current configuration will not be merged. Do you want to override it? [y/N] ', false);
+            $configure = $helper->ask($input, $output, $question);
+        } else {
+            $configure = true;
+        }
+
+        if ($configure) {
+            $output->writeln('');
+            $output->writeln(' 2.1 Security');
+            $output->writeln('-------------');
+
+            $token = str_shuffle(sha1(microtime().uniqid()));
+
+            $question = new ConfirmationQuestion('Registration enabled: [Y/n] ', true);
+            $enableRegistration = $helper->ask($input, $output, $question);
+
+            $question = new ConfirmationQuestion('Login enabled: [Y/n] ', true);
+            $enableLogin = $helper->ask($input, $output, $question);
+
+            $question = new ConfirmationQuestion('Login required to edit a gist: [y/N] ', false);
+            $loginRequiredToEditGist = $helper->ask($input, $output, $question);
+
+            $question = new ConfirmationQuestion('Login required to view a gist: [y/N] ', false);
+            $loginRequiredToViewGist = $helper->ask($input, $output, $question);
+
+            $question = new ConfirmationQuestion('Login required to view an embeded gist: [y/N] ', false);
+            $loginRequiredToViewEmbededGist = $helper->ask($input, $output, $question);
+
+            $output->writeln('');
+            $output->writeln(' 2.2 API');
+            $output->writeln('--------');
+
+            $question = new ConfirmationQuestion('API enabled: [Y/n] ', true);
+            $apiEnabled = $helper->ask($input, $output, $question);
+
+            if ($apiEnabled) {
+                $question = new ConfirmationQuestion('API key required: [y/N] ', false);
+                $apikeyRequired = $helper->ask($input, $output, $question);
+            } else {
+                $apikeyRequired = false;
+            }
+
+            $question = new Question('[Client] API base URL: [https://gist.deblan.org/] ', 'https://gist.deblan.org/');
+            $apiBaseUrl = $helper->ask($input, $output, $question);
+
+            $question = new Question('[Client] API key: [] ', '');
+            $apiClientApiKey = $helper->ask($input, $output, $question);
+
+            $configuration = [
+                'security' => [
+                    'token' => $token,
+                    'enable_registration' => $enableRegistration,
+                    'enable_login' => $enableLogin,
+                    'login_required_to_edit_gist' => $loginRequiredToEditGist,
+                    'login_required_to_view_gist' => $loginRequiredToViewGist,
+                    'login_required_to_view_embeded_gist' => $loginRequiredToViewEmbededGist,
+                ],
+                'api' => [
+                    'enabled' => $apiEnabled,
+                    'api_key_required' => $apikeyRequired,
+                    'base_url' => $apiBaseUrl,
+                    'client' => [
+                        'api_key' => $apiClientApiKey,
+                    ],
+                ],
+                'data' => [
+                    'path' => 'data/git',
+                ],
+                'git' => [
+                    'path' => '/usr/bin/git',
+                ],
+                'theme' => [
+                    'name' => 'dark',
+                ],
+            ];
+
+            $content = (new Yaml())->dump($configuration);
+
+            $done = file_put_contents('app/config/config.yml', $content);
+        }
+
+        $output->writeln('');
+        $output->writeln('Configuration finished!');
+    }
+
+    protected static function getPhp($includeArgs = true)
+    {
+        $phpFinder = new PhpExecutableFinder();
+        if (!$phpPath = $phpFinder->find($includeArgs)) {
+            throw new \RuntimeException('The php executable could not be found, add it to your PATH environment variable and try again');
+        }
+
+        return $phpPath;
+    }
+}