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Explain how to read and write large files using streams in Node.js

Q: Explain how to read and write large files using streams in Node.js

**TL;DR.** For large files use fs.createReadStream() and fs.createWriteStream() instead of readFile / writeFile . They process the file in **small chunks** (default ~64KB) so memory stays **constant** regardless of file size. Connect them with pipeline() , which handles backpressure and errors. createReadStream 64KB chunks pipeline() createWriteS

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Asks for a practical coding/architectural explanation of stream usage for file operations.

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Copy + compress a huge file

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

await pipeline(
  createReadStream('huge.csv'),
  createGzip(),
  createWriteStream('huge.csv.gz'),
);  // works for any size — memory stays flat

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