AUTHOR=Giusto Edoardo , Núñez-Corrales Santiago , Smith Kaitlin N. , Cao Phuong , Younis Ed , Rech Paolo , Vella Flavio , Baheri Betis , Cilardo Alessandro , Montrucchio Bartolomeo , Jiang Weiwen , Xu Shuai , Dasgupta Samudra , Iyer Ravishankar K. , Humble Travis S. 

TITLE=Dependable classical-quantum computing systems engineering

JOURNAL=Frontiers in Computer Science

VOLUME=Volume 7 - 2025

YEAR=2025

URL=https://www.frontiersin.org/journals/computer-science/articles/10.3389/fcomp.2025.1520903

DOI=10.3389/fcomp.2025.1520903

ISSN=2624-9898

ABSTRACT=Increasing evidence suggests quantum computing (QC) complements traditional High-Performance Computing (HPC) by leveraging its unique capabilities, leading to the emergence of a new, hybrid paradigm, QHPC. However, this integration introduces new challenges, with dependability–defined by reproducibility, resiliency, and security and privacy–emerging as a central concern for building trustworthy systems that provide an advantage to the users. This paper proposes a framework for dependable QHPC system design, organized around these three pillars. We identify integration challenges, anticipate roadblocks, and highlight productive synergies across QC, HPC, cloud platforms, and network security. Drawing from both classical computing principles and quantum-specific insights, we present a roadmap for co-design that supports robust hybrid architectures. Our approach offers concrete metrics for assessing dependability, provides design guidance for engineers working at the QC-HPC interface, and surfaces new engineering questions around complexity, scale, and fault tolerance. Ultimately, designing for dependability is key to realizing practical, scalable QHPC systems and accelerating the broader quantum ecosystem capable of translating quantum promises into actual application delivery.