Python-based replacement for xbacklight. It probably can be used as a drop-in replacement. Like the original, it uses the X11 RandR extension to get and set the display's backlight brightness. The main new feature is the ability to make adjustments in units smaller than one percent, e.g. xbacklight.py +0.2 to increase brightness by 0.2%.

Requirements: python (tested with 2.7 and 3.4), xcffib (or xpyb).