This package provides a completion command for a simple wiki. And I mean really simple: it’s just a folder with Org files which you can complete by name:
org-wiki ├── emacs.org ├── git.org ├── links.org ...
(require 'plain-org-wiki) (setq plain-org-wiki-directory "~/org/wiki")
plain-org-wiki gives you a list of all topics you have available
plain-org-wiki-directory. You can also add a new topic by selecting a name not
already on the list.