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CRDTs, Coalgebraically (Early Ideas)

Authors Nathan Liittschwager , Stelios Tsampas , Jonathan Castello , Lindsey Kuper

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Author Details

Nathan Liittschwager
  • University of California, Santa Cruz, CA, USA
Stelios Tsampas
  • Friedrich-Alexander-Universität Erlangen-Nürnberg, Germany
Jonathan Castello
  • University of California, Santa Cruz, CA, USA
Lindsey Kuper
  • University of California, Santa Cruz, CA, USA

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Nathan Liittschwager, Stelios Tsampas, Jonathan Castello, and Lindsey Kuper. CRDTs, Coalgebraically (Early Ideas). In 10th Conference on Algebra and Coalgebra in Computer Science (CALCO 2023). Leibniz International Proceedings in Informatics (LIPIcs), Volume 270, pp. 22:1-22:5, Schloss Dagstuhl - Leibniz-Zentrum für Informatik (2023)


We describe ongoing work that models conflict-free replicated data types (CRDTs) from a coalgebraic point of view. CRDTs are data structures designed for replication across multiple physical locations in a distributed system. We show how to model a CRDT at the local replica level using a novel coalgebraic semantics for CRDTs. We believe this is the first step towards presenting a unified theory for specifying and verifying CRDTs and replicated state machines. As a case study, we consider emulation of CRDTs in terms of coalgebra.

Subject Classification

ACM Subject Classification
  • Theory of computation
  • Theory of computation → Semantics and reasoning
  • Theory of computation → Distributed computing models
  • Theory of computation → Concurrency
  • Theory of computation → Formal languages and automata theory
  • Coalgebra
  • Distributed Systems
  • Concurrency
  • Bisimulation


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