Visualizers
Learn by moving things
Interactive explainers for the ideas behind retrieval, embeddings, and agents. A formula tells you what is true; dragging a vector shows you why. Each one also appears inside the article it belongs to, and runs entirely in your browser, so drag, poke, and break it.
Origin shield
From: CDNs: The Cache Nearest Your Users →When a popular file expires everywhere at once, every edge would hit the origin together. An origin shield is one mid-tier node all edges fetch through, so the origin sees a single request. The thundering herd at CDN scale.
Without a shield, when a popular file expires everywhere at once, every edge fetches it from the origin at the same moment. Five edges, five simultaneous origin hits.
A queue absorbs a rush
From: Message Queues: Work That Waits Its Turn →A checkout spike of 5,000 orders would melt a slow email step. A queue holds the backlog as depth and lets the worker drain it at a steady rate, so the spike becomes a short wait, not a crash. This is load leveling.
A calm minute: about 50 orders come in, and the email worker keeps up. The queue stays almost empty.
Competing consumers
From: Message Queues: Work That Waits Its Turn →Many workers read the same queue, and each message goes to exactly one of them. Add workers to drain a backlog faster: five hands clear in a fifth of the time, with no message handled twice.
One worker pulling the rail: 5,000 receipts at about 100 a second take roughly 50 seconds to clear.