I have posted a couple of novellas and 2 full novels a chapter at a time to Medium. A couple of years ago that was a more interesting thing to do than it is now. Medium has de-emphasized serialized fiction in distribution algorithms, unfortunately. Chapters of novels are no longer eligible for curation, so they don’t get as much attention as they used to.
I do still find the process valuable and I am posting a novel right now a chapter at a time. I get a lot of valuable feedback from readers as I work, and since I’m on my third draft, which is generally a boring and fairly lonely part of the writing process, I’m having more fun at this stage than I normally would.
As far as promotion goes, Linda George, I wouldn’t say this is all that productive. I promote my work on Medium on Facebook and Twitter rather than experiencing Medium as a promotion tool in its own right. My agent likes to see a my work develop a fan base there, though. She’s able to show potential publishers that the novel has the potential to engage loyal readers.
Here is a link to one of my last chapters:
