Luciano Xu enhanced the probabilistic rewrite mechanism in the EasyCrypt/easycrypt repository by focusing on memory safety and correctness. He implemented memory isolation checks to ensure that post-execution memory could not influence rewrite decisions, addressing a subtle but critical reliability concern. Additionally, Luciano introduced a validation function that prevents key variables from referencing post-execution memory, further strengthening the correctness of the rewrite path. Working primarily in OCaml and applying formal verification and functional programming techniques, he addressed a complex bug that reduced the risk of correctness issues and established a more robust foundation for future improvements to the rewrite pipeline.