This Festschrift, dedicated to Manuel Hermenegildo on the occasion of his 60th birthday, contains papers written by many of his closest collaborators. Manuel received his Ph.D. degree in Computer Science and Engineering from the University of Texas at Austin, and among various positions he was an endowed chair in Information Science and Technology at the University of New Mexico. In 2007 he became the founding director of the IMDEA Software Institute, where he is now a Distinguished Professor, while also a full professor at Universidad Politécnica de Madrid (UPM).
He has published more than 300 scientific publications, given numerous keynotes and invited talks at major conferences, coordinated many national and international projects, and served the community in major conference roles, on journal boards, and on funding, scientific, and research committees. Among his awards are the Julio Rey Pastor prize in Mathematics and Information Science and Technologyand the Aritmel prize in Computer Science; he is an elected member of the Academia Europaea; and in 2022 he was elected a Fellow of the ACM for contributions to program analysis, verification, parallelism, logic programming, and the IMDEA Software Institute.
Throughout his career, Manuel has been at the forefront of the fields of logic programming, constraint programming, parallel programming, program analysis, program transformation, and programming environment design. The contributions in this volume reflect the quality and the scope of his personal and collaborative successes.

Inhalt
Strategies in Conditional Narrowing Modulo SMT Plus Axioms.- Optimizing Maude Programs via Program Specialization.- Automated Synthesis of Software Contracts with KindSpec.- Abstract Interpretation of Graphs.- Applications of Muli: Solving Practical Problems with Constraint-Logic Object-Oriented Programming.- Grammar Induction for Under-resourced Languages: The Case of Ch'ol.- Answer Set Programming Made Easy.- The role of Abstraction in Model Checking.- Justifications and a Reconstruction of Parity Game Solving Algorithms.- SMT-based Test-Case Generation and Validation for Programs with Complex Specifications.- Layerings of Logic Programs - Layer Decomposable Semantics and Incremental Model Computation.- Modularization of Logic Programs.- Proof-theoretic Foundations of Normal Logic Programs.- A Discourse on Guessing and Reasoning.- Reversible Debugging in Logic Programming.- Towards Systematically Engineering Autonomous Systems using Reinforcement Learning and Planning.- StrandSpaces with Choice via a Process Algebra Semantics.