Emacs

Emacs is an actively developed open source text editor for code and prose old enough to have heirloom configuration files.1)

It has it's own wiki and stack exchange

Emacs advocates point to the lindy effect 2) and GNU community roots to argue Emacs is a safe investment. While, detractors point to the need for investing time to learn as a reason to avoid Emacs.

  • evil-mode for excellent vim emulation (modal editing povides a command grammar of editing)
  • dokuwiki-mode (see Emacs for wiki editing) for editing this wiki!
1)
Emacs predating common keyboard shortcuts. But it's defaults are the inspiration for many used by readline (bash, zsh shells) and nano.
2)
tech's “life expectancy” is proportional to it's current age.