The `dockerfiles` are derived images, that add or alter certain functionalities of the default docker images. In the `docker-compose` subfolder are examples for deployment of the application, including database, redis, collabora and other services.
[cron](https://github.com/nextcloud/docker/tree/master/.examples/dockerfiles/cron) | uses supervisor to run the cron job inside the container (so no extra container is needed).
[imap](https://github.com/nextcloud/docker/tree/master/.examples/dockerfiles/imap) | adds dependencies required to authenticate users via imap
[smb](https://github.com/nextcloud/docker/tree/master/.examples/dockerfiles/smb) | adds dependencies required to use smb shares
The advantage in adding this layer is the ability to add a container for [Let's Encrypt](https://letsencrypt.org/) certificate handling.
This combination of the [jwilder/nginx-proxy](https://github.com/jwilder/nginx-proxy) and [jrcs/docker-letsencrypt-nginx-proxy-companion](https://github.com/JrCs/docker-letsencrypt-nginx-proxy-companion) containers creates a fully automated https encryption of the nextcloud installation without worrying about certificate generation, validation or renewal.