Cells are the smallest living building blocks of our body. Although we do not notice this in our everyday life, there is constant activity deep inside our body: cells are frantically changing shape as they grow, divide and crawl through tissues. This activity is essential to support vital functions such as tissue repair and immune responses. The question of how cells achieve cell shape control has developed into a research area where concepts and methods taken from physics are employed: biophysics. After all, cellular shape changes involve physical properties like cell stiffness and deformability. In our lab at AMOLF, we study the physics of cell shape control by rebuilding synthetic cells in the lab from the ground up. The basic idea is to combine a minimal set of cellular components into a cell-like system, and test if this system can mimic cellular functions. We were able to generate cell-like systems that exhibit muscle-like contractions and shape changes. The next challenge is to create more realistic synthetic cells to understand more complex functionalities such as cell division. This would allow us to contribute to puzzles in biology and health science. At the same time, cells provide us with fascinating design concepts for new materials that can morph and move as cells do.