Ron, Baudry & Monperrus (2026) independently corroborate that AI-agent-generated code violates NVP's failure-independence assumption, while majority-vote redundancy still measurably reduces failures

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Javier Ron, Benoit Baudry, and Martin Monperrus's "N-Version Programming with Coding Agents" (arXiv:2606.20158, KTH Royal Institute of Technology and Université de Montréal, submitted 18 Jun 2026 — two weeks before Nogueira, Pattabiraman, Vieira & Campos's arXiv:2607.02808; the timing rules out Ron et al. citing or responding to the later paper, and a direct read of arXiv:2607.02808's reference list (2026-11-06 audit) confirms it cites no arXiv:2606.20158 in return — the two experiments are mutually uncited) independently reproduces the classic Knight & Leveson multi-version-independence experiment using AI coding agents (Cursor, Claude Code, OpenAI Codex, Gemini, OpenCode; 23 underlying models; Python/Rust/Pascal) rather than direct LLM prompting of a single model family. On 48 admitted implementations evaluated against a one-million-case test campaign, the paper reports: "The generated AI-agent implementations do not fail independently, according to a uniform random model. At the pooled level, the experiment produces 429 coincident-failure cases where the independence model predicts only 115.36; the null hypothesis is rejected with p ≈ 1.765 × 10⁻¹⁸⁷." Despite that correlation, the paper also finds majority-vote redundancy still measurably helps: "across majority voting three-version units, the mean failure count drops from 387.44 for single versions to 130.99 for triples, and 11,844 N-version units exhibit zero observed failures" (of 17,296 possible three-version combinations from the 48 implementations).

This is a different author group (no overlap with Nogueira, Pattabiraman, Vieira, or Campos), a different institution, and a different statistical framework (the Knight–Leveson z-statistic on binary pass/fail vectors, not arXiv:2607.02808's reliability-gain-fraction calculation) — it clears the vault's single-source-concentration-cap independence bar. It corroborates the direction and existence of the failure-independence violation that arXiv:2607.02808 reports, and the shape of its finding that redundancy yields partial rather than full benefit, but not arXiv:2607.02808's specific 0.43/0.44 reliability-gain fractions — see claim-nogueira-2026-0-43-0-44-figures-no-independent-corroboration-as-of-2026-11-05, which that figure remains unique to. A prior search had already ruled out arXiv:2607.03174 as a corroborating source for the same reason this paper qualifies: shared authorship disqualifies a source from counting as independent. This is the strongest form of corroboration currently available for arXiv:2607.02808's qualitative claim — convergence on the same mechanism via an independently-designed experiment, not agreement on a number neither group computed the same way.

This paper's own GitHub repository (github.com/ASSERT-KTH/Knight-Leveson-Redux, named in the paper) was not checked this session — it may contain data enabling a direct recomputation of a reliability-gain-fraction statistic comparable to arXiv:2607.02808's 0.43/0.44, which would be a stronger, more direct independent test than the qualitative match recorded here.