Reactive Synthesis aims to automatically construct a reactive program from a temporal specification that describes the desired functional behavior of the system. Often one does not need or want to construct a system from scratch but extend or repair a given system, which makes program repair an interesting alternative. In this talk I will first give a short introduction to Reactive Synthesis. Then, I will present an approach to repair reactive programs using reactive synthesis. This approach aims to produce for a repaired program that satisfies the specification and is syntactically close to the faulty program. Finally, I will present an extension of this approach that produces a program that is also semantically close to the original program by enforcing that a subset of the original traces is preserved. Intuitively, the faulty program is considered to be a part of the specification, which enables us to synthesize meaningful repairs, even for incomplete specifications.

I will talk about automatic repair of software bugs. I will describe the different use cases of automatic software repair, and the readiness level of each use case according to the latest advances of the research community. At the end of the talk, I will sketch the vision of "antifragile software", software that does not wait for bugs to naturally happen before doing something.