This example shows a full-stack web application architecture through a flowchart diagram rendered with Mermaid.js. The diagram organizes services into four labeled layers—Client, Application, Infrastructure, and External Providers—and connects them with directional arrows indicating relationships such as HTTP requests, database queries, and token verification. The code fetches the diagram definition from a separate `diagram.mermaid` file and renders it dynamically using Mermaid's JavaScript API, applying custom styling through Inconsolata font and theme variables. The implementation relies on `fetch` to load the source and `mermaid.render` to generate the SVG output.