vertex.degree hosts a freely available graph theory textbook written by Mikhail Lavrov. Unlike commercial course platforms, this is a straightforward personal project with no logins, payments, or data collection. The site uses robust encryption and hasn't appeared on any malware or phishing lists. Its domain history and a positive Hacker News discussion support its legitimacy. The main drawback today is technical: the website is returning a Cloudflare error, meaning the underlying server is not reachable. That's an availability issue, not a security one. For anyone looking for vertex.degree reviews, the key takeaway is that the project appears authentic and safe to use when the site comes back online. There's no reason to treat it as suspicious, just a temporary outage.
In plain English
This site is a legitimate personal textbook project, not a business or scam. It has strong security, no malware flags, and a real author behind it. The only issue at the moment is a technical outage — Cloudflare returned an error because the actual server isn't responding — so the site is currently down, not dangerous.
Where the score comes from
Strong encryption with a valid certificate from a trusted issuer, and modern TLS in use. No malware flags or blacklisting. The server still accepts older TLS versions, but that's a Cloudflare default and doesn't affect visitors.
The domain is a year old and owned through a privacy service, which is typical for individual projects. The author's name (Mikhail Lavrov) appears on the site, giving a clear human behind it.
Clean blacklist record, a year of web archive history, and a positive Hacker News mention (324 points) show the site has existed and been received well. No external complaints or abuse flags.
The site has an About page that explains the textbook and identifies the author. There's no contact page or social media links, but for a free, non-commercial project that's normal—authors often don't invite direct correspondence.
No privacy policy or terms of service, but this is a hobby/educational site with no e-commerce, logins, or data collection. Legal obligations don't apply, so the absence is not a concern.
Hosted on Cloudflare with solid email authentication (SPF, strict DMARC) and a valid certificate. No email handling is fine for a static site. DNSSEC isn't enabled, which is common for small sites and not a practical risk.
What we checked
Security & Transport
Certificate issued by Google Trust Services
X-Frame-Options: SAMEORIGIN
No threats detected by Google Web Risk
Server still accepts TLS 1.0/1.1 from clients that ask for them, which CDNs such as Cloudflare allow by default. Browsers stopped offering these versions in 2020, so visitors connect with TLS 1.2 or later
Cloudflare's malware-blocking resolver (1.1.1.2) answered normally for this domain. These resolvers refuse domains their threat intelligence lists for malware or phishing, and a scam only days old often isn't listed yet. Quad9 gave no usable answer.
Valid certificate, expires in 46 days
Web server: cloudflare
Connection uses TLS 1.3
Identity & WHOIS
Site publishes an About / Team / Company page — a transparency signal that the operator is willing to describe who runs the business.
Site has custom branding and social media metadata
No dedicated legal-entity disclosure page detected — common and expected outside the EU, but required for commercial sites in Germany, France, Spain, Italy, and other EU jurisdictions.
No contact page link, email address or phone number found on the homepage
Domain created 2025-09-25 (1 year, 1 month ago)
Expires in 332 days
No privacy policy or terms of service found — expected for commercial sites, normal for personal blogs and hobby projects
The registration shows a privacy service or redaction notice in place of the owner. Most registrars do this by default since GDPR (2018), for companies as well as individuals, so it hides nothing unusual.
Registered through Cloudflare, Inc
Infrastructure & DNS
Domain enforces strict DMARC — unauthenticated mail is rejected
Not listed by SpamCop and Barracuda, the blacklists that answered
Resolves to: 2a06:98c1:3121::2, 2a06:98c1:3120::2, 188.114.97.2, 188.114.96.2
Domain is not signed with DNSSEC
DNSSEC status from WHOIS
No MX records found — domain may not handle email
Hosted on: AS13335 CLOUDFLARENET (US)
DNS providers: damon.ns.cloudflare.com., jacqueline.ns.cloudflare.com.
Domain has SPF email authentication configured
Reputation & Reach
Hacker News readers only upvoted links to this site in 2026, and one burst of attention says less than interest over the years. The most upvoted, "Start Doing Graph Theory" (2026), got 324 points.
og:type declared as book
HTML declares lang="en"
No sitemap found — common for smaller sites
No social media links found on homepage
No structured data markup found
This site is not in the top 1 million most visited websites — this is normal for small or new businesses
Earliest archive snapshot from 20251008
Cloudflare answered with its own error page (HTTP 521) because it couldn't reach the site's server, which is down or misconfigured. The page is Cloudflare's, not the site's, so it wasn't inspected.
robots.txt has 2 directives
Other
Live homepage was blocked; content signals below reflect a Wayback Machine snapshot of the same URL. Treat as point-in-time evidence — the site existed and looked this way as of the snapshot date.
Run this site? Show your score.
Add a trust badge so visitors can see your live score for themselves.
Get your badge →