CCP4 (Collaborative Computational Project No. 4) uses IRIS infrastructure to support the development, testing and delivery of software used by the global structural biology community. The project develops and maintains the widely used CCP4 software suite, which is used to determine the three-dimensional structures of biological molecules from X-ray crystallography data collected at facilities such as Diamond Light Source and synchrotron laboratories worldwide. Through IRIS, CCP4 accesses computing resources that enable software development, automated testing, benchmarking and validation across a wide range of platforms and scientific workflows. IRIS infrastructure also supports the processing and analysis of crystallographic datasets, helping researchers work with increasingly large and complex experimental data collections. Beyond its direct use of computing resources, CCP4 contributes expertise in scientific software engineering, reproducible research and data management, benefiting both the structural biology community and the wider IRIS ecosystem.