Piotr Kula's answer seems to be on the right track but is outdated for Raspberry stretch.
There are updated instructions for uv4l on Raspberry stretch at
https://www.linux-projects.org/uv4l/installation/
# switch to superuser mode
sudo -s
# add the repository key for uv4l
curl http://www.linux-projects.org/listing/uv4l_repo/lpkey.asc | sudo apt-key add
# add the url for the u4vl repository to apt
echo "deb http://www.linux-projects.org/listing/uv4l_repo/raspbian/stretch stretch main" >> /etc/apt/sources.list
apt-get update
apt-get install uv4l uv4l-raspicam
apt-get install uv4l-raspicam-extras
reboot
You can tweek the uv4l options via /etc/uv4l/uv4l-raspicam.conf and then restart the service with
service uv4l_raspicam restart