  Decentralised cloud computing platforms enable individuals to offer and rent
resources in a peer-to-peer fashion. They must assign resources from multiple
sellers to multiple buyers and derive prices that match the interests and
capacities of both parties. The assignment process must be decentralised, fair
and transparent, but also protect the privacy of buyers. We present PASTRAMI, a
decentralised platform enabling trustworthy assignments of items and prices
between a large number of sellers and bidders, through the support of
multi-item auctions. PASTRAMI uses threshold blind signatures and commitment
schemes to provide strong privacy guarantees while making bidders accountable.
It leverages the Ethereum blockchain for auditability, combining efficient
off-chain computations with novel, on-chain proofs of misbehaviour. Our
evaluation of PASTRAMI using Filecoin workloads show its ability to efficiently
produce trustworthy assignments between thousands of buyers and sellers.
