Abstract Abstract This contribution deals with the problem of interoperability of blockchain technologies. Building on the framework offered by Lawrence Lessig, it will be argued that interoperability cannot be viewed as a simple matter of technological design. Blockchain technologies, in fact, give rise to complex ecosystems, which are shaped by both the architecture and social and market forces. The literature has mainly focused on the effects that the blockchain code has determined on the law of contracts. However, the action of the other modalities, in particular those of market and social forces and their interaction with the code has not been deeply investigated. By isolating the reciprocal effects of the different modalities of regulation—in particular, blockchain code and the law, blockchain code and the market, and blockchain code and social norms—this paper intends to fill this gap and sheds some more light on the internal dynamics of public blockchain. Finally, building on the insight so gained, we will explore the problem of interoperability between ledgers by analysing the pros and cons of the solution proposed so far.