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.@en

This paper presents the design, deployment and qualitative study of a large-scale, public, generative art exhibition, through which passers-by could create artworks, and mint a non-fungible-token (NFT). Following the month-long exhibition, during which 229 anonymous participants produced artworks, 69 non-transferable NFTs were minted, we surveyed (33) and interviewed (14) expert and novice participants about their experiences. We explored contemporary challenges of owning digital things, and the extent to which NFTs, and 'Web3' technologies offer meaningful forms of ownership. Our findings describe how the inability to trade this NFT, and its unique circumstances of acquisition, made it meaningful in ways that extended beyond its immediate (limited) utility and offered participants something through which to construct identity. Reflecting on the aspirations, contradictions, and misconceptions of forms of ownership enabled by NFTs, we conclude with proposals for renewed attention in HCI to the nature of digital possessions, and the potential for 'ownership design'.@en

This paper presents the design, deployment and qualitative study of a large-scale, public, generative art exhibition, through which passers-by could create artworks, and mint a non-fungible-token (NFT). Following the month-long exhibition, during which 229 anonymous participants produced artworks, 69 non-transferable NFTs were minted, we surveyed (33) and interviewed (14) expert and novice participants about their experiences. We explored contemporary challenges of owning digital things, and the extent to which NFTs, and 'Web3' technologies offer meaningful forms of ownership. Our findings describe how the inability to trade this NFT, and its unique circumstances of acquisition, made it meaningful in ways that extended beyond its immediate (limited) utility and offered participants something through which to construct identity. Reflecting on the aspirations, contradictions, and misconceptions of forms of ownership enabled by NFTs, we conclude with proposals for renewed attention in HCI to the nature of digital possessions, and the potential for 'ownership design'.@en

This paper presents the design, deployment and qualitative study of a large-scale, public, generative art exhibition, through which passers-by could create artworks, and mint a non-fungible-token (NFT). Following the month-long exhibition, during which 229 anonymous participants produced artworks, 69 non-transferable NFTs were minted, we surveyed (33) and interviewed (14) expert and novice participants about their experiences. We explored contemporary challenges of owning digital things, and the extent to which NFTs, and 'Web3' technologies offer meaningful forms of ownership. Our findings describe how the inability to trade this NFT, and its unique circumstances of acquisition, made it meaningful in ways that extended beyond its immediate (limited) utility and offered participants something through which to construct identity. Reflecting on the aspirations, contradictions, and misconceptions of forms of ownership enabled by NFTs, we conclude with proposals for renewed attention in HCI to the nature of digital possessions, and the potential for 'ownership design'.@en

This paper presents the design, deployment and qualitative study of a large-scale, public, generative art exhibition, through which passers-by could create artworks, and mint a non-fungible-token (NFT). Following the month-long exhibition, during which 229 anonymous participants produced artworks, 69 non-transferable NFTs were minted, we surveyed (33) and interviewed (14) expert and novice participants about their experiences. We explored contemporary challenges of owning digital things, and the extent to which NFTs, and 'Web3' technologies offer meaningful forms of ownership. Our findings describe how the inability to trade this NFT, and its unique circumstances of acquisition, made it meaningful in ways that extended beyond its immediate (limited) utility and offered participants something through which to construct identity. Reflecting on the aspirations, contradictions, and misconceptions of forms of ownership enabled by NFTs, we conclude with proposals for renewed attention in HCI to the nature of digital possessions, and the potential for 'ownership design'.@en

This paper presents GeoPact, an assembly of technological objects that materialises location-aware smart contracts using internet of things and digital ledger technologies. Such contracts may facilitate the creation of distributed systems and services for transport and logistics that are locally constructed and adaptable, thus supporting specific community needs and sustainable objectives. However the technological infrastructures that underpin these systems are complex, making it difficult to engage publics in design processes. GeoPact grounds infrastructure in relatable physical activities, that are linked with holistic views of the system, and creates new experiences for public engagement. In these activities participants were invited to roleplay as couriers, and to progress through delivery scenarios which were governed by smart contracts. Participants and spectators were then encouraged to discuss their reactions, concerns and ideas. This paper illustrates the GeoPact assembly and reflects on our engagement activities.@en

This paper presents GeoPact, an assembly of technological objects that materialises location-aware smart contracts using internet of things and digital ledger technologies. Such contracts may facilitate the creation of distributed systems and services for transport and logistics that are locally constructed and adaptable, thus supporting specific community needs and sustainable objectives. However the technological infrastructures that underpin these systems are complex, making it difficult to engage publics in design processes. GeoPact grounds infrastructure in relatable physical activities, that are linked with holistic views of the system, and creates new experiences for public engagement. In these activities participants were invited to roleplay as couriers, and to progress through delivery scenarios which were governed by smart contracts. Participants and spectators were then encouraged to discuss their reactions, concerns and ideas. This paper illustrates the GeoPact assembly and reflects on our engagement activities.@en

This paper presents GeoPact, an assembly of technological objects that materialises location-aware smart contracts using internet of things and digital ledger technologies. Such contracts may facilitate the creation of distributed systems and services for transport and logistics that are locally constructed and adaptable, thus supporting specific community needs and sustainable objectives. However the technological infrastructures that underpin these systems are complex, making it difficult to engage publics in design processes. GeoPact grounds infrastructure in relatable physical activities, that are linked with holistic views of the system, and creates new experiences for public engagement. In these activities participants were invited to roleplay as couriers, and to progress through delivery scenarios which were governed by smart contracts. Participants and spectators were then encouraged to discuss their reactions, concerns and ideas. This paper illustrates the GeoPact assembly and reflects on our engagement activities.@en

This paper presents GeoPact, an assembly of technological objects that materialises location-aware smart contracts using internet of things and digital ledger technologies. Such contracts may facilitate the creation of distributed systems and services for transport and logistics that are locally constructed and adaptable, thus supporting specific community needs and sustainable objectives. However the technological infrastructures that underpin these systems are complex, making it difficult to engage publics in design processes. GeoPact grounds infrastructure in relatable physical activities, that are linked with holistic views of the system, and creates new experiences for public engagement. In these activities participants were invited to roleplay as couriers, and to progress through delivery scenarios which were governed by smart contracts. Participants and spectators were then encouraged to discuss their reactions, concerns and ideas. This paper illustrates the GeoPact assembly and reflects on our engagement activities.@en

This paper presents an annotated portfolio of projects that seek to understand and communicate the social and societal implications of blockchains, DLTs and smart contracts. These complex technologies rely on human and technical factors to deliver cryptocurrencies, shared computation and trustless protocols but have a secondary benefit in providing a moment to re-think many aspects of society, and imagine alternative possibilities. The projects use design and HCI methods to relate blockchains to a range of topics, including global supply chains, delivery infrastructure, smart grids, volunteering and charitable giving, through engaging publics, exploring ideas and speculating on possible futures. Based on an extensive annotated portfolio we draw out learning for the design of blockchain systems, broadening participation and surfacing questions around imaginaries, social implications and engagement with new technology. This paints a comprehensive picture of how HCI and design can shape understandings of the future of complex technologies@en