Simple & Powerfull
This system has been used with adaptations in several role-playing games from Studio Deadcrows and Book In Game (INS/MV Génération Perdue, Aquablue, Donjons&Chatons, etc.). It also powers the role-playing game discovery booklet distributed by Asmodee.
Authors: Francois Cedelle, based on an original idea by CROC and with the help of Jeff, Batronoban, Philippe Auribeau, LG, and Trickytophe.
This complete game system is free and open source.
It is published under the Open Rpg Creative (ORC) license.
Come discuss it on the Studio Deadcrows Discord.