Besides the Dockerfile i also added a small patch to add some MIME-types to the webserver.
The Dockerfile uses a temporary build container to build a static version of darkhttpd (the binary is build against musl) and then copies over the binary into a scratch image.
The filesize of the final image is 627kB.
docker build --force-rm -t <reponame>/<imagename>:latest .
The container runs on port 8080 and uses an internal /data directory to serve the content
docker run -d --rm -p 8080:8080 -v <path/to/the/folder/you/want/to/serve>:/data <imagename>
You can also add more parameters to the server by adding them after the run command.
For a list of parameters visit the alpine wiki of darkhttpd.