Causally Consistent Reversible Choreographies

Under a reversible semantics, computation steps can be undone. Œis paper addresses the integration of reversible semantics into process languages for communication-centric systems, equipped with behavioral types. In prior work, we introduced a monitors-as-memories approach to seamlessly integrate reversible semantics into a process model in which concurrency is governed by session types (a class of behavioral types), covering binary (two-party) protocols with synchronous communications. Although such a model o‚ers a simple seŠing for showcasing our approach, its expressiveness is rather limited. Here we substantially extend our approach, and use it to de€ne reversible semantics for a very expressive processmodel that accounts formultiparty (n-party) protocols (choreographies), asynchronous communication, decoupled rollbacks, and process passing. As main technical result, we prove that our multiparty, reversible semantics is causally-consistent.