diff --git a/docker/php/Dockerfile b/docker/php/Dockerfile
index 8705ccf2..1e7600f7 100644
--- a/docker/php/Dockerfile
+++ b/docker/php/Dockerfile
@@ -83,7 +83,7 @@ COPY --from=composer /usr/bin/composer /usr/local/bin/composer
 COPY . /code
 
 # Install the compose depedencies.
-RUN cd /code && composer install
+RUN --mount=type=cache,target=/tmp/cache cd /code && composer install
 
 WORKDIR "/var/www"
 CMD [ "bootstrap.sh" ]