SolQDebug: Debug Solidity Quickly for Interactive Immediacy in Smart ContractDevelopment

As Solidity becomes the dominant language for blockchain smart contracts, efficient debugging grows increasingly critical. However, current Solidity debugging remains inefficient: developers must compile, deploy, set up transactions, and step through execution line-by-line to examine each variable. This process is too slow for practical use. To address this challenge, this paper presented SolQDebug, the first interactive source-level debugger for Solidity that delivered millisecond feedback directly on source code. Developers specify input value ranges through annotations and compare them against abstract interpretation results, thereby enabling exploration of contract behavior across multiple execution paths. SolQDebug was evaluated on 30 real-world functions from DAppSCAN, achieving 350$\times$ faster debugging (0.15s vs. 53s per function) than Remix IDE. The evaluation provided debugging insights: overlapping annotation patterns improved precision in most Solidity debugging scenarios, while analysis of diverse loop patterns demonstrated improved convergence while preserving soundness guarantees. These results demonstrated that SolQDebug enabled interactive debugging for Solidity development.