System D (in French, Système D) is a shorthand term that refers back to the French word débrouillard. The verb se débrouiller means "to untangle." The basic theory of System D is that it is a manner of responding to challenges that requires one to have the ability to think fast, to adapt, and to improvise when getting the job done. It has the connotation of getting around the system, managing to accomplish, or breaking the rules. Wikipedia
Système D is a common term used in Central Africa referring to adaptable, handy solutions. I found these images on Sandrine Dole's website, a french designer who lived in several countries in Africa, interesting images, patterns embodying the Système D!