Org mode

 Org mode  is for keeping notes, maintaining todo lists, planning projects, and authoring documents with a fast and effective plain-text system. Primarily used and designed for use in the emacs editor, Org mode extensions are available for other editors and operating systems.

IndieWeb Examples

 * Neil Mather has a commonplace at https://commonplace.doubleloop.net/ that is just basic in emacs using orgmode and org-roam and publishing it as static HTML from org-mode; My holy grail would be something like TiddlyWiki but in emacs.
 * Ryan Rix built an IndieWeb-enabled static-site generator on top of org-mode: Arcology.