First of all, thank you @jeromegn for this awesome tool / service.
I think it would make sense for DocumentUp to have an option to generate the docs from another file than README.md, like DOCS.md, as one may want to keep the README file small or to contain other information than the whole docs.
I imagine something like:
name: DocumentUp
file: DOCS.md
Could of course also be filepath or something similar.
Another question not worth opening a separate issue for:
is it possible to use .documentup.json instead of .documentup.yml? I saw this in https://github.com/wout/svg.js.