The File-server used by Planmap -- https://data.planmap.eu -- is customization of the Apache2 server by the Apaxy project with further modifications for Planmap.
For Planmap, a Markdown parser -- the Showdown javascript library --
was included to a proper rendering of the
README.md files included in each map package.
The customizations used by the project can be found at https://github.com/chbrandt/apaxy/tree/planmap.
Like the project's GeoServer, Planmap's File-server runs in a Docker container, found at https://cloud.docker.com/u/chbrandt/repository/docker/chbrandt/apaxy.
The File-server publishes data under /var/www/html.