DietPi | Minimal image at its core
Highly optimized minimal Debian OS
DietPi is extremely lightweight at its core, our images start at 400MB in size (3x lighter than 'Raspbian Lite'). With features of low process/memory footprint and DietPi-RAMlog installed by default, DietPi allows you to get the maximum performance from your device.
Now it support banana pi BPI-M1
more please see DietPi official:
Source code on github: