Complementing the overview contribution about the whitepaper on ultra-high-energy cosmic rays (UHECR) prepared for the Snowmass community survey in the U.S. [Astroparticle Physics 149 (2023) 102819 - arXiv:2205.05845], this contribution focuses on Chapter 6, the ‘Instrumentation Roadmap’ for UHECR physics in the next decades. In addition to an increase in statistics, a higher measurement accuracy of cosmic-ray air showers is needed to answer open questions regarding the astrophysics and particle physics related to UHECR. The needed boost in exposure can be provided by space-borne fluorescence detectors with POEMMA or by huge ground arrays using a single cost-effective technique, such as the giant radio arrays envisioned with GRAND. These observatories maximizing the exposure need to be complemented by ground arrays featuring an event-by-event resolution of the rigidity of the primary particle, which is the essence of GCOS. The required high mass resolution demands the simultaneous measurement of the electromagnetic (energy and $X_\mathrm{max}$) and muonic shower components, possibly by combining layered water-Cherenkov with radio detectors and next-generation fluorescence telescopes, together with novel analysis techniques, such as neural networks. The higher accuracy for air-shower measurements is also important for UHECR particle physics because it will enable stricter tests of hadronic interaction models and will help to identify ultra-high-energy photons or neutrinos. This contribution will give an overview of the instrumentation needed for the future of UHECR physics in the context of the next generation experiments discussed in the whitepaper.