GitLab B.V. CEO here. Lots of people use GitLab as the infrastructure to write books. Examples are PenFlip.com (using thier fork of GitLab) and all authoring for O'Reilly Media (their Atlas platform is the frontend.
Is this new to anyone? I have been using bit-bucket for writing a book for a couple of months. I figured this is pretty common. The Markdown language is great for writing technical material.
>> Right, wonderful, we could see how your story developed, if you had used line wrapping in your text editor. As is this diff is not at all informative.<p><a href="https://github.com/mcwm/novel_story/commit/e50c8ca7c583a65998a626d1912ded176e463f9f#commitcomment-9529159" rel="nofollow">https://github.com/mcwm/novel_story/commit/e50c8ca7c583a6599...</a>
Antreas Antonopoulos has been using Github for writting/editing Mastering Bitcoin (O'Reilly) as well<p><a href="https://github.com/aantonop/bitcoinbook" rel="nofollow">https://github.com/aantonop/bitcoinbook</a>