@Makyen [note: I have read Spencer's replies to you, but I otherwise have no information about Stack's specific implementation] As some additional technical context, CDNs can provide benefits to even personalized, uncacheable content - for example,
Amazon's Cloudfront's page on dynamic content delivery gives a case study of moving the Slack API (which the linked talk notes
does not use CDN caching) behind that CDN, resulting in significant latency improvements. Latency improvements can come from various sources, such as the fact that
creating a TLS connection involves 2-4 round trips (depending on TLS version, whether you've connected previously, etc.), so even just as little as terminating the TLS connection at the edge and then using an already established connection between the CDN and the backend can decrease latency significantly, especially for a company like Stack with a single hosting location.
