Introduction Modern web applications are no longer just simple static websites. Years ago, many websites were mostly: static pages blogs content websites simple request-response applications But modern software systems are very different. Today’s applications do things like: video uploads realtime notifications analytics processing AI inference payment processing image optimization email delivery realtime chat activity tracking stream processing Modern backend systems are now closer to continuously running software systems rather than just: “serve HTML and return response.” And this creates a very important architectural problem. The Problem With Long Running Tasks Suppose a user uploads a video. Your backend now needs to: save the file generate thumbnails compress the video notify followers update analytics scan for moderation Some of these tasks may take: several seconds minutes sometimes even longer Now imagine if the user had to wait for ALL of this before receiving a response.…