I3wm
Initial setup
I will assume you are working on a fresh, installation of Alpine standard. Otherwise see these instructions.
set up, and you are logged in as root.
Enable Community Repository
We need the Community Repository available for access to the i3 packages. Instructions are available on the Enable Community Repository page.
Install packages
Ensure you have the required drivers.
# apk search xf86-input*
# apk search xf86-video*
These are the drivers I needed but the ones you need might differ.
# apk add xf86-video-intel xf86-input-intel xf86-video-fbdev xf86-video-vesa
Install some fonts. If you start i3 without fonts it will be unusable.
# apk add terminus-font
Install i3, the i3 status bar and a terminal.
# apk add i3wm i3status xterm
Install dbus and set it up.
# apk add dbus
# dbus-uuidgen > /var/lib/dbus/machine-id
# rc-update add dbus
Install X11 and set it up.
# setup-xorg-base
Set up a non-root account. (Call this whatever you like.)
# adduser thomas
# addgroup thomas input
# addgroup thomas video
Now you can start i3 manually.
# startx /usr/bin/i3
Note: The default configuration is minimal and most menu options won't work unless you customize and/or install additional packages. More information is available in the i3 user guide.
To have i3 start automatically on login, you should set up xinit. There are different ways to do this. The arch wiki has good, transferrable information on this.