Smart contract systems could change the nature of last-mile deliv- ery for the better through enhanced precision, coordination and accountability. However, technological complexity poses a chal- lenge for end-users participating in the design process, making it hard to explore their experiences and incorporate their perspectives. We describe a case study where technological prototypes create smart contract experiences for professional couriers and receptionists, allowing them to speculate about emerging possibilities, whilst remaining grounded in their current practices. Participants enacted a series of deliveries, choreographed by smart contracts, and their responses were explored in post-experience, one-to-one interviews. Working with professionals to explore the potential impact of smart contract technologies, revealed the systemic webs of value underlying their existing work practices. This has implications for design of such technologies, in which increased automation, efciency and accountability must be delicately balanced with the benefts of sustaining personal values, relationships and agency.