Challenges and Practices in Quantum Software Testing and Debugging: Insights from Practitioners

TL;DR

This paper explores the unique challenges faced by quantum software developers in testing and debugging, revealing reliance on classical methods and highlighting the need for specialized tools to improve quantum software quality.

Contribution

It provides empirical insights from practitioners on current testing and debugging practices in quantum software engineering and identifies gaps in existing tools and workflows.

Findings

Most developers use classical testing methods over quantum-specific tools

Debugging relies on classical strategies like print statements and simulators

Bugs mainly stem from classical issues such as library updates and developer errors

Abstract

Quantum software engineering is an emerging discipline with distinct challenges, particularly in testing and debugging. As quantum computing transitions from theory to implementation, developers face issues not present in classical software development, such as probabilistic execution, limited observability, shallow abstractions, and low awareness of quantum-specific tools. To better understand current practices, we surveyed 26 quantum software developers from academia and industry and conducted follow-up interviews focused on testing, debugging, and recurring challenges. All participants reported engaging in testing, with unit testing (88%), regression testing (54%), and acceptance testing (54%) being the most common. However, only 31% reported using quantum-specific testing tools, relying instead on classical and manual methods. Debugging practices were similarly grounded in classical strategies, such as print statements, circuit visualizations, and simulators, which respondents noted do not scale well. The most frequently cited sources of bugs were classical in nature: library updates (81%), developer errors (69%), and compatibility issues (62%)-often worsened by limited abstraction in existing quantum SDKs. These findings highlight the urgent need for better-aligned testing and debugging tools integrated more seamlessly into the workflows of quantum developers. We present these results in detail and offer actionable recommendations grounded in the real-world needs of practitioners.