A team including Cluster researchers from the working groups of Principal Investigators Pavel Levkin and Wolfgang Wenzel present a 3D printable polymer gel system (PEGgel) with properties such as high stretchability and toughness, rapid self-healing, and long-term stability under ambient conditions. Soft materials like the reported PEGgel hold promises for broad applications in wearable electronics, soft actuators and robotics. The results are reported in Advanced Materials.