A personal wiki for Atom. See here.
What they say: "This project is based on the vimwiki package for vim, and strives for basic compatibility with that package. You should be able to point your awiki index to your vimwiki index and it should work just fine! Awiki supports only one wiki, which can be specified in the settings page. Pressing alt-w will open your wiki's index location. This can also be accessed from the main menu under Packages/Awiki/Open Wiki index." It uses free links.
I don't use Atom, so I have not tried it, but I thought someone might find this interesting! Nor have I ever tried Vimwiki. I doubt I ever will. No value judgment, but due to my limitations. I also suspect that the links will be broken when the target of the link is renamed. This seems to be a problem with all wikis that are based in an editor (including nVALt and Notetab).
1. I may be wrong about that. See here. But I am not sure I understand what the author of the blog claims. It may be only that if you change the name of a file on the index page, both the file referred to and the referring links get changed in Vimwiki.