diff --git a/src/Changelog.php b/src/Changelog.php
index 171f326..f957af2 100644
--- a/src/Changelog.php
+++ b/src/Changelog.php
@@ -108,7 +108,7 @@ public function generate(InputInterface $input, SymfonyStyle $output): int
             }
 
             // Generate new version code
-            $semver = new SemanticVersion('1.4.0-rc.1');
+            $semver = new SemanticVersion($lastVersion);
             $newVersion = $semver->bump($bumpRelease);
         }
 
diff --git a/src/SemanticVersion.php b/src/SemanticVersion.php
index 272b0ab..68d0e78 100644
--- a/src/SemanticVersion.php
+++ b/src/SemanticVersion.php
@@ -28,10 +28,8 @@ public function __construct($version)
 
     /**
      * Bump version.
-     *
-     * @param string $release
      */
-    public function bump($release): string
+    public function bump(string $release): string
     {
         $version = $this->getVersion();
 
diff --git a/src/Utils.php b/src/Utils.php
index 7d871a6..b554ff0 100644
--- a/src/Utils.php
+++ b/src/Utils.php
@@ -8,12 +8,8 @@ class Utils
 {
     /**
      * Clean string removing double spaces and trim.
-     *
-     * @param $string
-     *
-     * @return string
      */
-    public static function clean($string)
+    public static function clean(string $string): string
     {
         $string = trim($string);
 
@@ -24,10 +20,8 @@ public static function clean($string)
      *  Get today date string formatted.
      *
      * @param DateTime $today
-     *
-     * @return string
      */
-    public static function getDateString($date)
+    public static function getDateString(DateTime $date): string
     {
         $months = [
             'January',