Engineering, design, and product decisions written down so they're useful to someone other than the author six months later.
A practical breakdown of email open tracking inside Gmail — the pixel, the image proxy, deduplication, and the bot heuristics that determine whether an open is real.
Read the postThe smallest Gmail OAuth scope means we can't read your inbox, which means a few features are harder to build. We think the tradeoff is worth it. Here's the math.
Open tracking is the most popular metric in email and one of the noisiest. Click tracking is harder to get right but tells you more. Here's how we use both.