nightsaver is an OLED-friendly Xorg screensaver and PAM screen locker
written in Rust. It is a drop-in replacement for the xscreensaver daemon
and the xscreensaver-command control client: it accepts xscreensaver's
daemon flags, speaks its control protocol, and reads the relevant subset
of ~/.xscreensaver.

Every frame passes through an OLED guard that caps brightness, slowly
shifts pixels and periodically rests on a fully black screen. It ships
built-in clock, starfield, matrix and blank patterns, manages DPMS and
covers multiple monitors. Screen locking authenticates through OpenPAM
using unix-selfauth-helper, so nightsaver itself is not setuid.