Luigi Massacci developed a Lean formalization of Furstenberg’s proof of the infinitude of primes in the FormalBook repository, focusing on a topology refactor to enable more structured and robust formal reasoning. He reworked the proof to rely on a precise definition of topological spaces, which supports clearer theorem proving and lays groundwork for future mathematical extensions. Using Lean and applying skills in formal verification, number theory, and topology, Luigi also improved project documentation by correcting blueprint typos, reducing maintenance overhead. The work demonstrated depth in both mathematical formalization and codebase maintainability, addressing foundational aspects of mathematical logic and documentation clarity.