NitWings Insights

Technical Insights

Practical field notes for teams diagnosing email deliverability, DNS authentication, sender reputation, Linux, MTA, cloud, monitoring, and DevOps failures.

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Technical knowledge system connecting email identity, secure mail flow, servers, cloud operations, monitoring, and runbooks

182 Published articles

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Technical notes

Articles on email deliverability, DNS, Linux, MTA operations, DevOps, monitoring, and incident recovery.

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Short, practical guidance for teams that need to diagnose, repair, and run production email systems.

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Before-and-after diagram of Gmail’s December 12, 2013 image proxy change, separating direct recipient image requests from proxy fetching, caching, clicks and conversions

Email Deliverability · Dec 25, 2013 · 15 min read

Gmail Image Proxy in 2013: What Automatic Image Loading Changed for Marketers

A dated analysis of Gmail’s December 2013 secure image proxy, including automatic display, privacy, open tracking, dynamic images and current measurement practice.

Before-and-after diagram of Gmail’s May 29, 2013 change from one inbox view to Primary, Promotions, Social, Updates and Forums, with spam filtering and recipient attention shown separately

Email Deliverability · May 27, 2013 · 15 min read

Gmail Inbox Tabs in 2013: How Primary and Promotions Changed Email Visibility

A dated operational analysis of Gmail’s 2013 tabbed inbox, including Primary and Promotions classification, visibility, measurement, benefits, risks and current practice.