Build log · 16 October 2026
The empty page Google kept seeing
Written up in November 2026 from our engineering log · 2 min read
Some of our pages that read from the database were occasionally served empty — and the people seeing them most were search crawlers.
Built without data, cached per machine
Those pages were prerendered at build time and refreshed on a schedule. But the build has no database, so the prerendered copy was empty, and the cache lives on each server instance. Every new instance — dozens a week — served that empty copy once before refreshing.
Thirty days of logs put a number on it: about 10% of responses for the directory, 33% for the features documentation, and 13 of 790 sitemap responses to real crawlers were the empty version.
The fix
Pages fed by the database are now rendered per request, and their queries are memoised briefly so that does not cost much. A test fails the build if one of them is prerendered again.