NANO Macines to Structure Mars for Humans?

Perhaps Mars topology will be structured by nano machines used for building structures in dirt and hillsides one day. While biological contamination prophylaxis stops exploration in some areas where Martian life might grow, nano tech contamination might not present the same concerns; something to consider.  Danger from malreactive nano machines is another concern.  https://dailygalaxy.com/2026/01/the-special-regions-on-mars-where-it-is-totally-forbidden-to-explore-for-a-haunting-reason/