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What is the purpose of the 'zlib' module in Node.js?

Q: What is the purpose of the 'zlib' module in Node.js?

**TL;DR.** node:zlib provides **compression and decompression** — gzip, deflate, and **brotli** — as one-shot helpers and as **streams** you pipe through. Use it to shrink HTTP responses, compress stored data/backups, and read/write .gz files. CPU-heavy work is offloaded to the **libuv thread pool**. read stream createGzip() Transform <rect class='d-box-muted' x='354' y='5

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Tests knowledge of native compression tools to reduce network payloads.

zlibcompressionperformance

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Stream-compress a file to .gz

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

await pipeline(
  createReadStream('app.log'),
  createGzip({ level: 9 }),
  createWriteStream('app.log.gz'),
);  // constant memory, non-blocking (thread pool)

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