Quoting Paul Gilmartin via tz on Wednesday July 08, 2026:
... While the -latest versions will necessarily have some minor lag in updating for this reason, the new releases with the version number embedded will always be up-to-date as their filename is novel. ...
Can the If-Modified-Since and if-none-match request headers help to resolve this?
I don't think so. The benefit of a CDN is to offload traffic from the origin servers by caching it for some period of time without rechecking if the content has changed. If the CDN nodes always checked back to the origin upon every request to check for freshness, it would defeat much of the purpose plus likely add intolerable latency. Yes, headers like If-Modified-Since would reduce the traffic, but it would still be blocking on a downstream call back to home.
But how many servers respect these? And how many clients even understand them?
I'd hope most modern HTTP implementations have this baked in! If you are a consumer of the -latest files, definitely use these headers when polling for updates to avoid unnecessarily pulling down the file when it hasn't changed. kim