To react to unforeseen circumstances or amend abnormal situations in communication-centric systems, programmers are in charge of "undoing" the interactions which led to an undesired state. To assist this task, session-based languages can be endowed with reversibility mechanisms. In this paper we propose a language enriched with programming facilities to commit session interactions, to roll back the computation to a previous commit point, and to abort the session. Rollbacks in our language always bring the system to previous visited states and a rollback cannot bring the system back to a point prior to the last commit. Programmers are relieved from the burden of ensuring that a rollback never restores a checkpoint imposed by a session participant different from the rollback requester. Such undesired situations are prevented at design-time (statically) by relying on a decidable compliance check at the type level, implemented in MAUDE. We show that the language satisfies error-freedom and progress of a session.

@article{paperbot3458,
  title = {Checkpoint-based rollback recovery in session programming},
  author = {Claudio Antares Mezzina and Francesco Tiezzi and Nobuko Yoshida},
  journal = {Logical Methods in Computer Science},
  volume = {Volume 21, Issue 1},
  year = {2025},
  doi = {10.46298/lmcs-21(1:2)2025}
}