diff --git a/Dockerfile b/Dockerfile
index 2e2c204..b9f1a2f 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -13,7 +13,7 @@ COPY ./scripts /scripts
 RUN apk --no-cache add php7 php7-fpm php7-json php7-zlib php7-xml php7-phar php7-iconv php7-mcrypt curl php7-curl php7-openssl php7-gd && \
   mkdir -p ${PHP_PID_DIR}/ && \
   chown ${NGINX_RUN_USER}:${NGINX_RUN_GROUP} ${PHP_PID_DIR}/ && \
-  curl -sS https://getcomposer.org/installer | php -- --install-dir=${COMPOSER_PATH} --filename=composer && \
+  curl -sS https://getcomposer.org/installer | php -- --1 --install-dir=${COMPOSER_PATH} --filename=composer && \
   cp /conf/nginx/app.conf /etc/nginx/conf.d/app.conf && \
   cp /conf/php/app-php.ini /etc/php7/conf.d/zz_app.ini && \
   cp /conf/php/app-php-fpm.conf /etc/php7/php-fpm.d/zz_app.conf && \