What powers jeffser.com?

Last seen Sep 2026 · 8 technologies across 6 categories

Analytics

Caching

Varnish
since Sep 2024

CDN

Cloudflare
since Sep 2024
Fastly
since Sep 2024
jsDelivr
since Apr 2026

Miscellaneous

HTTP/3
since Sep 2024

PaaS

GitHub Pages
since Sep 2024

UI frameworks

Tailwind CSS
since Apr 2026

AI Crawlers

Blocks 8 of 33 AI crawlers we track by name in its robots.txt. Checked Sep 2026. A recent check saw a policy file missing; awaiting confirmation.

Training crawlers

  • Applebot-Extended Blocked
  • Bytespider Blocked
  • CCBot Blocked
  • ClaudeBot Blocked
  • Google-Extended Blocked
  • GPTBot Blocked
  • meta-externalagent Blocked

Search and AI assistants

  • Amazonbot Blocked

The other 25 AI crawlers we track are not mentioned and stay allowed by default.

  • robots.txt found
  • llms.txt not found
  • ai.txt not found

Content Signals: search=yes ai-train=no declared in robots.txt

See who blocks each AI crawler across the web

AI Crawlers

8 of 33 AI crawlers blocked

Standards: Content Signals

Full breakdown

Open Page Rank

3.02 / 10 · ranked #1,547,759 of all domains

28 referring domains · OpenPageRank

Page

  • CDN: Cloudflare, Fastly
  • Weight: 0.1 MB · 11 requests

Homepage as crawled by the HTTP Archive, Oct 2026.

Infrastructure

  • Hosted on Cloudflare (104.21.84.193, IPv6)
  • DNS: Cloudflare DNS
  • Email: no MX record returned
  • Email security: SPF (hard fail), DMARC reject
  • SSL: Google Trust Services, ECDSA P256, wildcard, expires Oct 2026
  • Common Crawl link graph: rank 1,151,418
  • Verified with: Google

DNS records as swept Aug 2026, certificate as seen Sep 2026. How the web is hosted

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