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Field notes from the build.

Debugging post-mortems, infrastructure deep dives, and hard-won lessons from shipping web systems that have to actually stay up.

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DNS Web Infrastructure Debugging

DNS_PROBE_FINISHED_NXDOMAIN: When Your Two Nameservers Disagree

A site that loaded on some devices and died on others. It wasn't propagation, it wasn't a registrar hold — it was two authoritative nameservers quietly serving different versions of the same zone. Here's how to catch it with dig.

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June 1, 20269 min read