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.