Caching the uncacheable in Varnish - Thijs Feryn - NDC Oslo 2024

This talk was recorded at NDC Oslo in Oslo, Norway. #ndcoslo #ndcconferences #developer #softwaredeveloper Attend the next NDC conference near you: https://ndcconferences.com https://ndcoslo.com/ Subscribe to our YouTube channel and learn every day: / @NDC Follow our Social Media! https://www.facebook.com/ndcconferences https://twitter.com/NDC_Conferences https://www.instagram.com/ndc_conferences/ #devops #web #http When the pressure is on, your application will need to scale up or scale out. Throwing servers at the problem is not a sustainable solution and refactoring is not always effective. Caching, on the other hand, might reduce the impact of your application on the system. Unfortunately, when personalization comes into play, caching is really hard: it’s a tradeoff between caching enough variations of your content and maintaining a good hit rate. In this presentation, we will use different techniques in Varnish to cache personalized content: * Using HTTP fragments such as ESI and AJAX * Creating cache variations using cookie values * Authentication on the edge * Fetching session data on the edge * Content transformation and personalization on the edge By doing as much decision making and transformation “on the edge”, we avoid performing expensive computing at the origin, which allows us to scale and to “cache the uncacheable”.