This book presents reflections on the occasion of 20 years on the KeY project that focuses on deductive software verification. Since the inception of the KeY project two decades ago, the area of deductive verification has evolved considerably. Support for real world programming languages by deductive program verification tools has become prevalent. This required to overcome significant theoretical and technical challenges to support advanced software engineering and programming concepts. The community became more interconnected with a competitive, but friendly and supportive environment. We took the 20-year anniversary of KeY as an opportunity to invite researchers, inside and outside of the project, to contribute to a book capturing some state-of-the-art developments in the field. We received thirteen contributions from recognized experts of the field addressing the latest challenges. The topics of the contributions range from tool development, effciency and usability considerations to novel specification and verification methods. This book should offer the reader an up-to-date impression of the current state of art in deductive verification, and we hope, inspire her to contribute to the field and to join forces. We are looking forward to meeting you at the next conference, to listen to your research talks and the resulting fruitful discussions and collaborations.

This book presents reflections on the occasion of 20 years on the KeY project that focuses on deductive software verification. Since the inception of the KeY project two decades ago, the area of deductive verification has evolved considerably. Support for real world programming languages by deductive program verification tools has become prevalent. This required to overcome significant theoretical and technical challenges to support advanced software engineering and programming concepts. The community became more interconnected with a competitive, but friendly and supportive environment. We took the 20-year anniversary of KeY as an opportunity to invite researchers, inside and outside of the project, to contribute to a book capturing some state-of-the-art developments in the field. We received thirteen contributions from recognized experts of the field addressing the latest challenges. The topics of the contributions range from tool development, effciency and usability considerations to novel specification and verification methods. This book should offer the reader an up-to-date impression of the current state of art in deductive verification, and we hope, inspire her to contribute to the field and to join forces. We are looking forward to meeting you at the next conference, to listen to your research talks and the resulting fruitful discussions and collaborations.

The papers of this volume focus on the foundational aspects of computer science, the thematic origin and stronghold of LNCS, under the title “Computing and Software Science: State of the Art and Perspectives”. They are organized in two parts: The first part, Computation and Complexity, presents a collection of expository papers on fashionable themes in algorithmics, optimization, and complexity. The second part, Methods, Languages and Tools for Future System Development, aims at sketching the methodological evolution that helps guaranteeing that future systems meet their increasingly critical requirements. Chapter 3 is available open access under a Creative Commons Attribution 4.0 International License via link.springer.com.

This four-volume set LNCS 13701-13704 constitutes contributions of the associated events held at the 11th International Symposium on Leveraging Applications of Formal Methods, ISoLA 2022, which took place in Rhodes, Greece, in October/November 2022. The contributions in the four-volume set are organized according to the following topical sections: specify this - bridging gaps between program specification paradigms; x-by-construction meets runtime verification; verification and validation of concurrent and distributed heterogeneous systems; programming - what is next: the role of documentation; automated software re-engineering; DIME day; rigorous engineering of collective adaptive systems; formal methods meet machine learning; digital twin engineering; digital thread in smart manufacturing; formal methods for distributed computing in future railway systems; industrial day.

This book constitutes the proceedings of the 17th International Conference, TAP 2023, as part of STAF 2023, a federation of conferences on Software Technologies, Applications and Foundations, which includes two more conferences besides TAP: ICGT (International Conference on Graph Transformations), and ECMFA (European Conference on Modelling Foundations and Applications) in Leicester, UK, in July 2023. The 8 full papers together with 2 short papers included in this volume were carefully reviewed and selected from 14 submissions. They were organized in topical sections on Low-level Code Verification, Formal Models, Model-based test generation, and Abstraction and Refinement.

This Festschrift, dedicated to Reiner Hähnle on the occasion of his 60th birthday, contains papers written by many of his closest collaborators. After positions at Karlsruhe Institute of Technology and Chalmers University of Technology, since 2011 Reiner has been the chaired professor of Software Engineering at Technische Universität Darmstadt, where his team focuses on the formal verification of object-oriented software, the formal modeling and specification of highly adaptive software systems, and formal modeling and analysis in domains such as biological systems and railroad operations. His work is characterized by achievements in theory and in practical implementations, significant collaborations include the KeY project and the development of the ABS language. He has served as chair and editor of important related academic conferences, and coauthored almost 200 academic publications. The contributions in this volume reflect Reiner’s main research focus: formal methods, in particular applied to software verification.