diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index d598bca..d3e3a7d 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -11,7 +11,7 @@ services:
 
 test:7:
     before_script:
-      - bash ./build/docker_install.sh > /dev/null
+      - bash build/docker_install.sh > /dev/null
       - curl -sS https://getcomposer.org/installer | php
       - php composer.phar install --no-dev
     image: php:7
@@ -20,7 +20,7 @@ test:7:
       
 test:7.1:
     before_script:
-      - bash ./build/docker_install.sh > /dev/null
+      - bash build/docker_install.sh > /dev/null
       - curl -sS https://getcomposer.org/installer | php
       - php composer.phar install --no-dev
     image: php:7.1
diff --git a/build/docker_install.sh b/build/docker_install.sh
new file mode 100644
index 0000000..8690f16
--- /dev/null
+++ b/build/docker_install.sh
@@ -0,0 +1,38 @@
+#!/bin/bash
+
+# We need to install dependencies only for Docker
+[[ ! -e /.dockerenv ]] && [[ ! -e /.dockerinit ]] && exit 0
+
+# Where am I?
+DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
+
+set -xe
+
+# Install git (the php image doesn't have it) which is required by composer
+apt-get update -yqq
+apt-get install \
+	git \
+	unzip \
+	libfreetype6 \
+	libjpeg62-turbo \
+	libmcrypt4 \
+	libpng12-0 \
+	libfreetype6-dev \
+	libjpeg-dev \
+	libmcrypt-dev \
+	libpng12-dev \
+	libxslt1-dev \
+	libxslt1.1 \
+	zlib1g-dev \
+	-yqq
+
+# Install phpunit, the tool that we will use for testing
+curl -Lo /usr/local/bin/phpunit https://phar.phpunit.de/phpunit.phar
+chmod +x /usr/local/bin/phpunit
+
+# Install extensions
+docker-php-ext-install apcu
+docker-php-ext-install memcache
+docker-php-ext-install memcached
+docker-php-ext-install xsl
+docker-php-ext-install zip
\ No newline at end of file