diff --git a/box.json.dist b/box.json.dist
new file mode 100644
index 0000000..03c7861
--- /dev/null
+++ b/box.json.dist
@@ -0,0 +1,4 @@
+{
+  "force-autodiscovery": true,
+  "output": "poser.phar"
+}
\ No newline at end of file
diff --git a/docker/php-fpm/Dockerfile b/docker/php-fpm/Dockerfile
index e9413e7..7daceee 100644
--- a/docker/php-fpm/Dockerfile
+++ b/docker/php-fpm/Dockerfile
@@ -9,15 +9,12 @@ RUN apt-get update \
     && apt-get -y --no-install-recommends install php-xdebug php7.4-bcmath php7.4-gd php7.4-intl php-msgpack php-yaml \
     && apt-get clean; rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/* /usr/share/doc/*
 
-# Install git
+# Install git and wget
 RUN apt-get update \
-    && apt-get -y install git \
+    && apt-get -y install git wget \
     && apt-get clean; rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/* /usr/share/doc/*
 
-RUN mkdir -p /home/dev/.composer \
-    && chown -R 1000:1000 /home/dev/
+COPY --from=composer:2 /usr/bin/composer /usr/local/bin/composer
 
-ENV COMPOSER_CACHE_DIR='/home/dev/.composer'
-
-# Install prestissimo
-RUN composer global require hirak/prestissimo
+## To generate phar archive: https://github.com/box-project/box
+RUN wget -q -O /usr/bin/box https://github.com/box-project/box/releases/download/3.11.0/box.phar && chmod +x /usr/bin/box
diff --git a/poser.phar b/poser.phar
new file mode 100755
index 0000000..6bf7414
Binary files /dev/null and b/poser.phar differ
diff --git a/src/Calculator/GDTextSizeCalculator.php b/src/Calculator/GDTextSizeCalculator.php
index 07e0c19..7308216 100644
--- a/src/Calculator/GDTextSizeCalculator.php
+++ b/src/Calculator/GDTextSizeCalculator.php
@@ -28,6 +28,7 @@ public function __construct()
     public function calculateWidth(string $text, int $size = self::TEXT_SIZE): float
     {
         $size = $this->convertToPt($size);
+        var_dump($this->fontPath);
         $box  = \imagettfbbox($size, 0, $this->fontPath, $text);
 
         return \round(\abs($box[2] - $box[0]) + self::SHIELD_PADDING_EXTERNAL + self::SHIELD_PADDING_INTERNAL, 1);