You can edit this website using GitHub pull request.
Most of the content is generated from the _data diretory or the individual html pages.
If you are editing this website locally, you can try rendering it with Docker, e.g.:
docker run -it -e PAGES_REPO_NWO=workflowscommunity/workflowscommunity.github.io \
--volume=`pwd`:/srv/jekyll -p 4000:4000 jekyll/jekyll jekyll serve
Note that you will also need to execute scripts/process_systems.py manually with Python to recreate the workflow system pages from GitHub.