Inspectable Control for Structure-Preserving Software Regeneration Gavrilov, Alexey Alexey Gavrilov https://orcid.org/0009-0006-3147-5430 ITMO University, Saint Petersburg, Russian Federation Gazzaev, Alan-Barsag Alan-Barsag Gazzaev https://orcid.org/0009-0000-0334-312X ITMO University, Saint Petersburg, Russian Federation Mozikov, Mikhail Mikhail Mozikov https://orcid.org/0000-0003-0594-867X AXXX, Moscow, Russian Federation Makarov, Ilya Ilya Makarov https://orcid.org/0000-0002-3308-8825 AXXX, Moscow, Russian Federation Muravyov, Sergey Sergey Muravyov https://orcid.org/0000-0002-4251-1744 ITMO University, Saint Petersburg, Russian Federation 10.1145/3803437.3807386 979-8-4007-2636-1 2026-07-05 eng ACM conference paper Software-engineering workflows such as constrained repair, staged refinement, and structure-preserving modification require control over what changes and what remains fixed. Token-level generation is a weak control surface for these operations because it constrains local surface text rather than the coarse structural invariants that software engineering often aims to preserve. We study hierarchical discrete latents as an inspectable intermediate representation for software artifacts: a hierarchical VQ-VAE compresses a 64-token Python function into coarse and fine discrete codes, and masked discrete generation regenerates only selected positions under partial constraints. On 2,000 preprocessed Python functions, locking four top-level codes improves parse rate from 0.453 to 0.591 while preserving substantial change in unlocked positions (edit freedom, 0.936) and near-maximal sample uniqueness (diversity, 0.998). Under fixed coarse context, lower-level refinement is weaker but remains monotonic, supporting a coarse-to-fine reading of the hierarchy. Overall, these results provide early evidence for a practical control layer that supports bounded, structure-preserving software-artifact regeneration above the token level. text/html application/pdf https://aogavrilov.com/publications/inspectable-control/ open access software artifact control hierarchical discrete latents structure-preserving regeneration partial code regeneration masked discrete generation software engineering Automatic programming Software maintenance tools Creative Commons Attribution 4.0 International AM https://aogavrilov.com/publications/inspectable-control/paper.pdf Proceedings of the 34th ACM International Conference on the Foundations of Software Engineering 1406 1407