diff --git a/Dockerfile b/Dockerfile
index fcbdfa8..d7932b3 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,19 +1,19 @@
 FROM php:7.4-apache
 
-RUN a2enmod rewrite
+SHELL ["/bin/bash", "-o", "pipefail", "-c"]
 
+# hadolint ignore=DL3008
 RUN set -xe \
     && apt-get update \
-    && apt-get install -y \
+    && apt-get install --no-install-recommends -y \
         # PHP dependencies
         libfreetype6-dev libpng-dev libjpeg-dev libpq-dev libxml2-dev \
         # New in PHP 7.4, required for mbstring, see https://github.com/docker-library/php/issues/880
         libonig-dev \
-        # To clone plugins
-        git \
     && docker-php-ext-configure gd --with-jpeg --with-freetype \
     && docker-php-ext-install gd mbstring mysqli soap \
-    && rm -rf /var/lib/apt/lists/*
+    && rm -rf /var/lib/apt/lists/* \
+    && a2enmod rewrite
 
 ENV MANTIS_VER 2.24.1
 ENV MANTIS_MD5 a5a001ffa5a9c9a55848de1fbf7fae95
@@ -22,32 +22,33 @@ ENV MANTIS_FILE mantisbt.tar.gz
 
 # Install MantisBT itself
 RUN set -xe \
-    && curl -fSL ${MANTIS_URL} -o ${MANTIS_FILE} \
-    && md5sum ${MANTIS_FILE} \
+    && curl -fSL "${MANTIS_URL}" -o "${MANTIS_FILE}" \
+    && md5sum "${MANTIS_FILE}" \
     && echo "${MANTIS_MD5}  ${MANTIS_FILE}" | md5sum -c \
-    && tar -xz --strip-components=1 -f ${MANTIS_FILE} \
-    && rm ${MANTIS_FILE} \
+    && tar -xz --strip-components=1 -f "${MANTIS_FILE}" \
+    && rm "${MANTIS_FILE}" \
     && rm -r doc \
     && chown -R www-data:www-data . \
     # Apply PHP and config fixes
     # Use the default production configuration
     && mv "$PHP_INI_DIR/php.ini-production" "$PHP_INI_DIR/php.ini" \
-    && echo 'mysqli.allow_local_infile = Off' >> $PHP_INI_DIR/conf.d/mantis.php.ini \
-    && echo 'display_errors = Off ' >> $PHP_INI_DIR/conf.d/mantis.php.ini \
-    && echo 'log_errors = On ' >> $PHP_INI_DIR/conf.d/mantis.php.ini \
-    && echo 'error_log = /dev/stderr' >> $PHP_INI_DIR/conf.d/mantis.php.ini \
-    && echo 'register_argc_argv = Off' >> $PHP_INI_DIR/conf.d/mantis.php.ini
+    && echo 'mysqli.allow_local_infile = Off' >> "$PHP_INI_DIR/conf.d/mantis.php.ini" \
+    && echo 'display_errors = Off ' >> "$PHP_INI_DIR/conf.d/mantis.php.ini" \
+    && echo 'log_errors = On ' >> "$PHP_INI_DIR/conf.d/mantis.php.ini" \
+    && echo 'error_log = /dev/stderr' >> "$PHP_INI_DIR/conf.d/mantis.php.ini" \
+    && echo 'register_argc_argv = Off' >> "$PHP_INI_DIR/conf.d/mantis.php.ini"
 
 COPY config_inc.php /var/www/html/config/config_inc.php
 
 # Install additional plugins
-# TODO: copy from multi-stage to remove git dependency
 ENV SOURCE_TAG v2.3.1
 RUN set -xe && \
-        git clone --branch $SOURCE_TAG --depth 1 https://github.com/mantisbt-plugins/source-integration.git /tmp/source && \
+        curl -fSL https://github.com/mantisbt-plugins/source-integration/tarball/${SOURCE_TAG} -o /tmp/source.tar.gz && \
+        mkdir /tmp/source && \
+        tar -xz --strip-components=1 -f /tmp/source.tar.gz -C /tmp/source/ && \
         cp -r /tmp/source/Source /tmp/source/SourceGitlab /tmp/source/SourceGithub /var/www/html/plugins/ && \
         rm -r /tmp/source
 
-ADD ./mantis-entrypoint /usr/local/bin/mantis-entrypoint
+COPY ./mantis-entrypoint /usr/local/bin/mantis-entrypoint
 
 CMD ["mantis-entrypoint"]