diff --git a/docker/Dockerfile-test b/docker/Dockerfile-test
index 516936f..5828139 100644
--- a/docker/Dockerfile-test
+++ b/docker/Dockerfile-test
@@ -1,4 +1,11 @@
-FROM php:7.4.7-cli-buster
+FROM ubuntu:focal
 
-RUN apt-get update && apt-get install -y git unzip
-RUN curl -sS https://getcomposer.org/installer | php -- --install-dir=/usr/local/bin --filename=composer
+ENV DEBIAN_FRONTEND noninteractive
+
+# Install PHP and further necessary packages
+RUN apt update --fix-missing
+RUN apt install -y git unzip php7.4-cli
+
+# Install Composer
+COPY scripts/install-composer.sh install-composer.sh
+RUN ./install-composer.sh