All below package names are from the Arch repositories. Some packages are exclusive to the AUR only.

Required packages

the bare minimum of this setup

xorg-server                 - I don't use Wayland and almost nothing on this list supports it.
windowmaker                 - The desktop. Self explanatory.
wmclock                     - The clock, you'd be a loser without one.
wmsystemtray                - Support for XDG tray icons, required for many applications.

Optional packages

part of xinitrc or basic utils

kitty                       - OpenGL 3.2 terminal emulator.
picom                       - Compositor for drop shadows and hardware-accelerated rendering.
kmix                        - KDE's Qt frontend for ALSA.
xscreensaver                - Screensaver pack for X server by Jamie Zawinski.
ckb-next                    - Free software reimplementation of Corsair iCUE for select keyboards.
protonmail-bridge           - Local IMAP server for encrypted Proton accounts.