GNU Robbo is a free and open source implementation of Janusz Pelc's
Robbo for the Atari XE/XL, which was distributed by LK Avalon in
1989.

This script will build it without support for TrueType fonts by
default. If you want to enable it, please pass variable
TTFONTS=yes to the script but be aware that this will link against
SDL_ttf.
