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https://interestingengineering.com

Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
100
GRADE
A+
FIX
0
REVIEW
1
PASS
8
INFO
0
Probed from Amsterdam, Netherlands
200 OK
Checks
9
8 PASS 1 REVIEW
B
TLS Certificate Expiry & Recommendations
84 days until leaf cert expires — 3 issues to address
REVIEW

Certificate validity

84
days left
0d 30d 60d 90d+

Recommended actions

  • Enable HSTS: Strict-Transport-Security: max-age=31536000; includeSubDomains
  • Enable DNSSEC on your domain for DNS spoofing protection
  • Enable OCSP stapling on your TLS server to remove a CA roundtrip and protect user privacy
A+
DNS Records
2 A records, 8 ms lookup
PASS
2 A records, 8 ms lookup
Info::
Resolves to 2 IPv4 address(es)
Got: 104.20.25.137, 172.66.155.11
Info::
Has 2 IPv6 (AAAA) record(s)
Got: 2606:4700:10::6814:1989, 2606:4700:10::ac42:9b0b
Info::
2 nameserver(s) configured
Got: junade.ns.cloudflare.com, sue.ns.cloudflare.com
Info::
5 mail exchanger(s) configured
Info::
CAA records not checked
CAA record lookup requires a specialized DNS resolver. This check will be available in a future update.
Info::
SPF record present in TXT
Info::
DNS resolution time: 8 ms
Got: 8 ms
A104.20.25.137, 172.66.155.11
AAAA2606:4700:10::6814:1989, 2606:4700:10::ac42:9b0b
CNAME—
NSjunade.ns.cloudflare.com, sue.ns.cloudflare.com
MX
1 aspmx.l.google.com
5 alt1.aspmx.l.google.com
5 alt2.aspmx.l.google.com
10 alt3.aspmx.l.google.com
10 alt4.aspmx.l.google.com
TXT
ahrefs-site-verification_bb6f2832711ffaa212a3a46e40fa481ab56103faa9d6ae5a6c227a3...
amazonses:BsFZnMpfphbTI4cLy7p2D7U09D0PmDdrCayPKo9CNtM=
ca3-eb2e5807496f46d29e464114f0668ec6
facebook-domain-verification=r0xji9myxx8zvihfou0byd6trit9vx
google-site-verification=KY7V7yHesnEVyhAYZNxnsMioUnPkiTn_PmMFld0z9I8
google-site-verification=Ka6xvWi3AgqPpDxqBpDiCt5Sh8Ql96WXuhfLljFInGs
google-site-verification=PK5fcyhiwiHIBhDBLg7ootM_gGS_fykP0WDmSs9JKWM
google-site-verification=PVs5qtlN1mSg7_QWe8mPSaJv_qknu_cS1OFeDGXdSIo
google-site-verification=lIf7R4E6nYXpC0Z_4fG1FjuKRtFgaHJ2VjfoU161pmM
include:47062935.spf03.hubspotemail.net
SPF v=spf1 include:_spf.google.com include:spf.braintreegateway.com include:spf.mand...
CAALookup not available with standard resolver
Resolved in 8 ms

CAA record lookup requires a specialized DNS resolver. This check will be available in a future update.

Why this matters

Informational: CAA (Certification Authority Authorization) records weren't checked in this scan.

A+
Redirect Chain
No redirects — direct access
PASS
No redirects — direct access
Info::
No redirects — direct access
Got: https://interestingengineering.com

https://interestingengineering.com

46 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://interestingengineering.com20046 msHTTP/1.1cloudflare
A+
IPv6 Readiness
IPv6 reachable (1 ms)
PASS
IPv6 reachable (1 ms)
Info::
IPv6 is configured and reachable at 2606:4700:10::6814:1989, 2606:4700:10::ac42:9b0b
Got: 1 ms connect
IPv6 Ready
AAAA Records 2606:4700:10::6814:1989, 2606:4700:10::ac42:9b0b Connection Reachable (1 ms)
A+
Crawlability
robots.txt present, sitemap with 73 URLs
PASS
robots.txt present, sitemap with 73 URLs
Info::
robots.txt is present
Got: 2598 bytes
Info::
sitemap.xml is present
Info::
sitemap.xml is valid XML
Info::
sitemap.xml contains 73 entries
Info::
Sitemap index with 73 child sitemaps
Info::
robots.txt references sitemap
robots.txt 200 OK
Size 2598 B Sitemaps referenced 2 User-agents *, AI2Bot, Amazonbot, ClaudeBot, Diffbot, iaskspider/2.0, ICC-Crawler, ImagesiftBot, DuckAssistBot, FacebookBot, FriendlyCrawler, ISSCyberRiskCrawler, omgilibot, Kangaroo Bot, Meta-ExternalAgent, Ai2Bot-Dolma, Applebot-Extended, CCBot, cohere-ai, facebookexternalhit, img2dataset, Meta-ExternalFetcher, PetalBot, Scrapy, VelenPublicWebCrawler, Webzio-Extended, YouBot, omgili, Claude-Web, Google-Extended, Sidetrade indexer bot, Timpibot, anthropic-ai, Bytespider Blocking No — crawling allowed
User-agent: *
Disallow: /s/*
Disallow: /redir/*
Disallow: /partial/*
Disallow: /*?context_item_id
Disallow: /search
Disallow: /signup
Disallow: /newsletters/
Disallow: /*?group=test_a
Disallow: /*?group=test_b

Disallow: /newsletters/engineer-pros/
Allow: /newsletters/engineer-pros
Allow: /newsletters/engineer-pros/subscribe

Disallow: /newsletters/ie-originals/
Allow: /newsletters/ie-originals
Allow: /newsletters/ie-originals/subscribe

Disallow: /newsletters/mechanical/
Allow: /newsletters/mechanical
Allow: /newsletters/mechanical/subscribe

Disallow: /newsletters/electrical/
Allow: /newsletters/electrical
Allow: /newsletters/electrical/subscribe

Disallow: /newsletters/ai-logs/
Allow: /newsletters/ai-logs
Allow: /newsletters/ai-logs/subscribe

Disallow: /newsletters/aerospace/
Allow: /newsletters/aerospace
Allow: /newsletters/aerospace/subscribe

Disallow: /newsletters/software/
Allow: /newsletters/software
Allow: /newsletters/software/subscribe

Disallow: /newsletters/sustainability/
Allow: /newsletters/sustainability
Allow: /newsletters/sustainability/subscribe

Disallow: /newsletters/the-blueprint/
Allow: /newsletters/the-blueprint
Allow: /newsletters/the-blueprint/subscribe

Disallow: /reviews/

User-agent: AI2Bot
Disallow: /

User-agent: Ai2Bot-Dolma
Disallow: /

User-agent: Amazonbot
Disallow: /

User-agent: anthropic-ai
Disallow: /

User-agent: Applebot-Extended
Disallow: /

User-agent: Bytespider
Disallow: /

User-agent: CCBot
Disallow: /

User-agent: Claude-Web
Disallow: /

User-agent: ClaudeBot
Disallow: /

User-agent: cohere-ai
Disallow: /

User-agent: Diffbot
Disallow: /

User-agent: DuckAssistBot
Disallow: /

User-agent: FacebookBot
Disallow: /

User-agent: facebookexternalhit
Disallow: /

User-agent: FriendlyCrawler
Disallow: /

User-agent: Google-Extended
Disallow: /

User-agent: iaskspider/2.0
Disallow: /

User-agent: ICC-Crawler
Disallow: /

User-agent: ImagesiftBot
Disallow: /

User-agent: img2dataset
Disallow: /

User-agent: ISSCyberRiskCrawler
Disallow: /

User-agent: Kangaroo Bot
Disallow: /

User-agent: Meta-ExternalAgent
Disallow: /

User-agent: Meta-ExternalFetcher
Disallow: /

User-agent: omgili
Disallow: /

User-agent: omgilibot
Disallow: /

User-agent: PetalBot
Disallow: /

User-agent: Scrapy
Disallow: /

User-agent: Sidetrade indexer bot
Disallow: /

User-agent: Timpibot
Disallow: /

User-agent: VelenPublicWebCrawler
Disallow: /

User-agent: Webzio-Extended
Disallow: /

User-agent: YouBot
Disallow: /

Sitemap: https://interestingengineering.com/sitemap_index.xml
Sitemap: https://interestingengineering.com/news-sitemap.xml
sitemap.xml 200 OK
Type Sitemap Index URLs 73 entries Valid XML Yes
Child Sitemaps:
A+
URL Variants
www/non-www, trailing slash, HTTP→HTTPS
PASS
www/non-www, trailing slash, HTTP→HTTPS
Info::
www/non-www redirect configured correctly (preferred: non-www)
Info::
HTTP correctly 301-redirects to HTTPS

www / non-www

301https://www.interestingengineering.com/
200https://interestingengineering.com/

Preferred variant: non-www

HTTP → HTTPS

301http://interestingengineering.com/ → https://interestingengineering.com/

Consistent

A+
Domain Intelligence
interestingengineering.com — via GoDaddy.com, LLC, 14 years, 8 months old
PASS
interestingengineering.com — via GoDaddy.com, LLC, 14 years, 8 months old
Info::
Domain registered until Nov 4, 2033 (7 years, 7 months remaining)
Info::
DNSSEC is not enabled
DNSSEC protects against DNS spoofing attacks. While not required, enabling DNSSEC adds an additional layer of security. Contact your DNS provider to enable it.
Info::
Registrar: GoDaddy.com, LLC
Warning::
Registrar lock is NOT enabled
The domain can be transferred without an unlock step. Enable registrar lock (clientTransferProhibited) in your registrar's control panel to protect against unauthorized or accidental transfers.
Domain expiry

2666 days

November 4, 2033

SSL certificate

84 days

Issued by Let's Encrypt

Domain age

14 years, 8 months

Registered November 4, 2011

DNSSEC

Not enabled

Protects against DNS spoofing

Hosting

Unknown

2606:4700:10::6814:1989

Registrar

GoDaddy.com, LLC

Unlocked 2 NS records
Expiry timeline
Today
+1 year
Domain expiry SSL expiry Danger zone (≤30 days)
Recommended actions
  • Enable DNSSEC to protect visitors from DNS spoofing
  • Enable registrar lock (clientTransferProhibited) to block unauthorized domain transfers
Registrar GoDaddy.com, LLC
Created November 4, 2011 (14 years, 8 months ago)
Expires November 4, 2033 (7 years, 7 months)
Last Updated January 4, 2024
Name Servers junade.ns.cloudflare.com, sue.ns.cloudflare.com
DNSSEC Not enabled
Hosting
IP Address 2606:4700:10::6814:1989
Data source: rdap (0.0s)

DNSSEC protects against DNS spoofing attacks. While not required, enabling DNSSEC adds an additional layer of security. Contact your DNS provider to enable it.

Why this matters

Without DNSSEC, an attacker who can poison your DNS can hijack your domain — and SSL certs alone don't stop them.

Learn more ▾

DNSSEC adds cryptographic signatures to DNS records, preventing forged responses from poisoning resolver caches. Without it, an attacker who controls the network path can redirect your domain to a malicious server before any HTTPS handshake happens. Most modern registrars (Cloudflare, Google Domains, Route 53) enable it with one toggle.

Source: ICANN / RFC 4033

The domain can be transferred without an unlock step. Enable registrar lock (clientTransferProhibited) in your registrar's control panel to protect against unauthorized or accidental transfers.

Why this matters

Without registrar lock, an attacker who phishes your registrar credentials can transfer the domain in minutes — total brand hijack.

Learn more ▾

Registrar lock (clientTransferProhibited, clientUpdateProhibited, clientDeleteProhibited) requires extra verification before any transfer/update/delete. Every major registrar offers it free. Combined with 2FA on your registrar account, it's the strongest defense against domain hijacking.

Source: ICANN / domain-security best practice

A+
HTTP Probe Timing
Total 46 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
5 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
1 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
7 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
42 ms
Total Time Total request time from DNS lookup through full response.
46 ms

Connection waterfall

DNS Lookup 5 ms TCP Connect 1 ms TLS Handshake 7 ms Server Processing 29 ms Content Transfer 4 ms
A
CDN & Delivery
Cloudflare (DYNAMIC)
PASS
Cloudflare (DYNAMIC)
Info::
Site is served via Cloudflare CDN (edge: AMS)
Got: cf-ray: 9f0009b9be1aae32-AMS
Info::
CDN cache status: DYNAMIC
CDN Detected: Cloudflare
Provider Cloudflare Cache Status DYNAMIC Evidence cf-ray: 9f0009b9be1aae32-AMS
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

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