The Pek Window Manager is written by Claes Nasten, the code is based
on the aewm++ window manager, but it has evolved enough that it no
longer resembles aewm++ at all.
It has a much expanded feature-set, including window grouping (similar
to ion, pwm, or fluxbox), autoproperties, xinerama, keygrabber that
supports keychains, and much more.

o Lightweight and Unobtrusive, a window manager shouldn't be noticed.
o Very configurable, we all work and think in different ways.
o Automatic properties, for all the lazy people, make things appear as
  they should when starting applications.
o Chainable Keygrabber, usability for everyone.

WWW: https://www.pekwm.se/