# Compression

> Compression is an Agent Skill for testing & quality published in the thedaviddias/Front-End-Checklist repository on GitHub: a SKILL.md instruction file an AI agent can load to do this task.

Use when auditing slow page loads, heavy assets, or rendering delays related to Enable text-based compression. Verify the actual bottleneck in DevTools, Lighthouse, or field data before recommending changes.

- Skill name: `compression`
- Category: [Testing & Quality](https://www.openparable.com/skill/testing-quality/1)
- Source: https://github.com/thedaviddias/Front-End-Checklist/blob/HEAD/skills/compression/SKILL.md
- Repository: thedaviddias/Front-End-Checklist (73,218 GitHub stars when collected)

## SKILL.md

# Enable text-based compression

Compressed assets download faster, reducing the time to first paint and improving the overall perceived performance, especially on slower mobile networks.

## Quick Reference

- Use Gzip or Brotli to compress text resources (HTML, JS, CSS)
- Brotli provides superior compression for modern browsers
- Significantly reduces data transfer size and load times
- Compression helps network cost, but it does not remove parse and execution cost from oversized bundles

## Check

Verify that text-based resources are served with `Content-Encoding: gzip` or `br` headers.

## Fix

Enable Gzip or Brotli compression in your web server (Nginx, Apache) or CDN settings.

## Explain

Explain how text-based compression works and its impact on asset delivery speed.

## Code Review

Review the routes, assets, and loading behavior that affect Enable text-based compression. Flag exact files, requests, or rendering steps that add unnecessary network, CPU, or layout cost, and describe the measurement method used to confirm the issue.

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For full implementation details, code examples, and framework-specific guidance,
see `references/rule.md`.

Rule page: https://frontendchecklist.io/en/rules/performance/compression

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Source: https://www.openparable.com/skill/testing-quality/compression (OpenParable). Cite the canonical URL above.