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What are Node.js Streams and when would you use them?

Q: What are Node.js Streams and when would you use them?

**TL;DR.** **Streams** process data **chunk-by-chunk** instead of loading it all into memory. There are four types — **Readable**, **Writable**, **Duplex**, and **Transform** — all built on EventEmitter . Use them for large files, network I/O, and pipelines where buffering everything would be slow or blow up memory. Readable source Transform gzip/parse <path class='d-edge-accent' d='M294 77 H342' ma

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Tests knowledge of efficient data handling in Node.js.

streamsi/operformancedata handling

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Stream + transform a file to a response

import { createReadStream } from 'node:fs';
import { createGzip } from 'node:zlib';
import { pipeline } from 'node:stream/promises';

await pipeline(
  createReadStream('big.log'),  // Readable
  createGzip(),                 // Transform
  res,                          // Writable (HTTP response)
);  // constant memory, backpressure handled, errors propagated

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