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Explain the concept of 'event-driven architecture' in Node.js.

Q: Explain the concept of 'event-driven architecture' in Node.js.

**TL;DR.** **Event-driven architecture (EDA)** structures a program around **producing and reacting to events** rather than calling functions directly. Node embodies this: the **event loop** dispatches I/O completion events, and EventEmitter lets your components emit/observe domain events — decoupling producers from consumers. order service upload handler <text class='d-

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This question explores a core architectural paradigm that Node.js heavily relies on.

event-drivenarchitectureevent loopscalability

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Decoupled reactions to one domain event

import { EventEmitter } from 'node:events';
const bus = new EventEmitter();

// Producer doesn't know who reacts:
function placeOrder(o) { bus.emit('order.created', o); }

// Independent consumers:
bus.on('order.created', (o) => sendConfirmationEmail(o));
bus.on('order.created', (o) => trackAnalytics('order', o));

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