[{"data":1,"prerenderedAt":64},["ShallowReactive",2],{"\u002Fglossary\u002Fservice-worker":3,"\u002Fglossary\u002Fservice-worker:related":47},{"id":4,"title":5,"author":6,"authorImage":7,"body":8,"category":32,"date":33,"description":34,"draft":35,"extension":36,"letter":37,"meta":38,"navigation":39,"path":40,"readTime":41,"related":42,"seo":43,"stem":45,"term":5,"__hash__":46},"glossary\u002Fglossary\u002Fservice-worker.md","Service Worker","Fabian Krumbholz","\u002Fimages\u002Fauthors\u002Ffabian-krumbholz.webp",{"type":9,"value":10,"toc":28},"minimark",[11],[12,13,14,15,19,20,23,24,27],"p",{},"A service worker is a script that runs in the background in a user's web browser, separate from the web page. It acts as a programmable network proxy, giving a website the ability to intercept and handle network requests. Speed Kit uses the service worker as its core client-side technology to enable its most powerful features, including ",[16,17,18],"strong",{},"Dynamic Caching",", ",[16,21,22],{},"Dynamic Content Merging",", and ",[16,25,26],{},"Predictive Preloads",", all directly on the user's device.",{"title":29,"searchDepth":30,"depth":30,"links":31},"",2,[],null,"April 8, 2026","A service worker is a script that runs in the background in a user's web browser, separate from the web page. It acts as a programmable network proxy, giving a website the ability to intercept and…",false,"md","S",{},true,"\u002Fglossary\u002Fservice-worker","1 min read",[],{"title":44,"description":34},"Service Worker: Definition | Web Performance Glossary","glossary\u002Fservice-worker","fjBy_hZm-D6esQCMiB4vAT8hbHnPlrsKSla_oyqgt7c",[48,52,56,60],{"path":49,"title":50,"description":51,"letter":37},"\u002Fglossary\u002Fsearch-engine-optimization-seo","Search Engine Optimization (SEO)","SEO is the process of improving a website's visibility in search engine results pages (like Google). The goal is to rank higher than competitors for relevant search queries to attract more organic (free) traffic.",{"path":53,"title":54,"description":55,"letter":37},"\u002Fglossary\u002Fserver-response-time","Server Response Time","Server Response Time is a component of Time to First Byte that measures how long the server takes to process a request and start sending back a response, excluding network latency.",{"path":57,"title":58,"description":59,"letter":37},"\u002Fglossary\u002Fserver-timing","Server Timing","Server Timing is a browser API that allows the backend to communicate performance metrics about its own internal processes (e.g., database query time, time to render a component) to the browser via HTTP headers.",{"path":61,"title":62,"description":63,"letter":37},"\u002Fglossary\u002Fserver-side-ab-testing","Server-Side A\u002FB Testing","This is a performance-friendly method for running A\u002FB tests. Unlike Client-Side A\u002FB Testing, the decision of which variation to show a user is made on the Origin Server.",1787756716046]