This is the source for the Home-Assistant.io website.
Setting up to contribute to documentation and the process for submitting pull requests is explained here
In order to make the preview available on http://127.0.0.1:1313, use the command as follows:
hugo serve -w
Or, using Docker,
docker build -t ha-hugo . && docker run --rm -it -v $(pwd):/src -p 1313:1313 ha-hugo