diff --git a/docker/Dockerfile b/docker/Dockerfile
index 974bf4936..841a23460 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -11,7 +11,9 @@ COPY . /srv/www
 WORKDIR /srv/www
 
 # Clean up previous composer installation and run new one.
-RUN rm -rf ./vendor && composer install --no-interaction --no-dev
+RUN rm -rf ./vendor && \
+    composer self-update && \
+    composer install --no-interaction --no-dev
 
 # Copy settings to default site location.
 RUN cp -a docker/settings.php docker/services.yml docker/memcache.services.yml html/sites/default