$ ls -l /dev/ttyUSB0 crw-rw---- 1 root dialout 188, 0 Nov 5 22:08 /dev/ttyUSB0 $ sudo adduser nat dialout # replace "nat" with your username
After adding a user to a group, you need to completely relog. Probably best to just reboot.
Need a more recent version than in Debian/Ubuntu repos.
Arduino instructions here: