About

The author

Arachnide is written by Thierry Gustin, freelance SEO consultant and French teacher based in Madrid. He built it for his own technical SEO audits and shares it freely with the SEO community.

Profiles: GitHub · thierrygustin.com · LinkedIn.

License

Arachnide SEO Spider is published under the MIT license, © 2026 Thierry Gustin. You are free to use, modify and share it, including for commercial work. The Inter font bundled with the application and this site is published under the SIL Open Font License 1.1.

Contributing

Bug reports, ideas and pull requests are welcome, in English, French, German or Spanish. The contributing guide explains how to propose a change, add an SEO check (one call in src/analyze.mjs plus labels in the six translation files) and fix a translation. Run npm test before opening a pull request: it fails if a key or a placeholder is missing in any language.

Reporting a bug

Open an issue on GitHub with your operating system and Node.js version (node -v), the steps to reproduce it, the URL you crawled if it is public, and the error shown in the terminal or the browser console.

This website

This site is a static site generated with Astro. Its documentation, reference tables and changelog are generated from the Arachnide repository so that they cannot drift from the code. It uses no third-party tracker; see the legal and privacy page.