A Concurrent Perspective on Smart Contracts

Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10323)


In this paper, we explore remarkable similarities between multi-transactional behaviors of smart contracts in cryptocurrencies such as Ethereum and classical problems of shared-memory concurrency. We examine two real-world examples from the Ethereum blockchain and analyzing how they are vulnerable to bugs that are closely reminiscent to those that often occur in traditional concurrent programs. We then elaborate on the relation between observable contract behaviors and well-studied concurrency topics, such as atomicity, interference, synchronization, and resource ownership. The described contracts-as-concurrent-objects analogy provides deeper understanding of potential threats for smart contracts, indicate better engineering practices, and enable applications of existing state-of-the-art formal verification techniques.



Sergey’s research is supported by EPSRC grant EP/P009271/1. Hobor’s research is funded by Yale-NUS College R-607-265-045-121.


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Copyright information

© International Financial Cryptography Association 2017

Authors and Affiliations

  1. 1.University College LondonLondonUK
  2. 2.Yale-NUS College and School of ComputingNational University of SingaporeSingaporeSingapore

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