Living cells are highly sophisticated computational machines, constantly processing information to survive, grow and reproduce. If we could program cells as effectively as we program digital computers, we could make fundamental breakthroughs in health and energy production, while also gaining insight into the workings of life itself. However, the task of programming cells is extremely complex, and we are at a point now where powerful computer software is needed to accelerate further progress. This demo presents our initial efforts in developing computer software for programming cells, together with preliminary experimental results. The software allows the desired behaviour of a molecular device to be programmed, simulated, analysed and then automatically compiled to DNA code, which could then be inserted into cells to reprogram their behaviour. In the same way that software for programming digital computers heralded a new era of technology, we anticipate that software for programming living cells could pave the way for a biotechnological revolution.