We are witnessing a technological revolution in type 1 diabetes, with a race to bring commercial closed-loop (artificial pancreas) systems to market. However, only one automated insulin-delivery system, the Medtronic MiniMed 670G, has received both US Food and Drug Administration (FDA) and European CE mark approval and is commercially available in several countries. The French Diabeloop system, designed to work with several continuous glucose monitors and insulin pumps, has received a CE mark, and the FDA have awarded the Tandem Diabetes Care t:slim X2 the status of an alternate controller enabled interoperable pump, facilitating efficient premarket review; however, neither are commercially available yet. Meanwhile, in the European Union, new medical device regulations will be more demanding with respect to safety, potentially slowing access to commercial closed-loop systems. While waiting for these systems to come to market, people living with diabetes have taken development into their own hands, with the #WeAreNotWaiting movement supporting the use of do-it-yourself (DIY) artificial pancreas systems incorporating commercially available insulin pumps and continuous glucose monitors with automated control algorithms. Several DIY artificial pancreas systems are now available for people to build and use, integrating a range of different insulin pumps and glucose sensors. Health-care professional opinions of DIY artificial pancreas systems in the UKType 1 diabetes is one of the most challenging long-term medical conditions to manage. Over the past five years, technologically skilled people with type 1 diabetes have developed communication systems and algorithms that allow insulin delivery from insulin pumps to be automatically controlled. These systems combine glucose data from a continuous glucose monitor with an original algorithm that communicates with an insulin pump to sustain, reduce, or increase insulin delivery to maintain glucose levels within a target range. Full-Text PDF