Thanks :) No CDN actually -- it's just a side project served straight from a single VPS at the moment. You're probably just seeing the speed of response cachin

Thanks :) No CDN actually -- it's just a side project served straight from a single VPS at the moment. You're probably just seeing the speed of response caching (which I've written in Crystal too, using Redis and local disk as storage backends). If you request a new ticker symbol that isn't already cached, or specify custom date ranges, it will recompute or even have to fetch data from upstream data provider, and those requests will take a bit longer. Also, the whole site is currently served up as a single HTTP request, except for a few external JS and CSS files (Bootstrap, uPlot) which are served from public CDNs.