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https://svelte.dev

Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
87
GRADE
B
FIX
0
REVIEW
3
PASS
6
INFO
0
Probed from Santa Clara, United Stated
200 OK
Checks
9
6 PASS 3 REVIEW
C
IPv6 Readiness
Action
No IPv6 support
REVIEW
No IPv6 support
Info::
No IPv6 (AAAA) records found
IPv6 support is increasingly important for global accessibility. About 40% of internet users have IPv6 connectivity.
No IPv6 Support
About 40% of internet users have IPv6. Consider adding AAAA records.

IPv6 support is increasingly important for global accessibility. About 40% of internet users have IPv6 connectivity.

Why this matters

No AAAA records — same impact as 'no IPv6 (AAAA) records'; IPv6-preferring clients pay extra latency falling back to IPv4.

Source: Google IPv6 stats

B
Crawlability
robots.txt present, no sitemap
REVIEW
robots.txt present, no sitemap
Info::
robots.txt is present
Got: 24 bytes
Info::
No sitemap.xml found
A sitemap helps search engines discover and index your pages more efficiently.
Info::
robots.txt does not reference a sitemap
Add a 'Sitemap:' directive to robots.txt so search engines can discover your sitemap.

A sitemap helps search engines discover and index your pages more efficiently.

Why this matters

No sitemap.xml — Google relies on crawl-graph discovery alone, slowing indexing of deep or fresh URLs.

Learn more

A sitemap accelerates Google's discovery of new and updated content. Most CMSes auto-generate one; static-site frameworks need a build-step plugin. Reference it from robots.txt and submit in Search Console to confirm Google can fetch it.

Source: sitemaps.org / Google Search Central

Add a 'Sitemap:' directive to robots.txt so search engines can discover your sitemap.

Why this matters

robots.txt omits Sitemap: directive — crawlers must fetch /sitemap.xml by convention; reliable but missing the explicit hint.

Source: sitemaps.org

robots.txt 200 OK
Size 24 B Sitemaps referenced 0 User-agents * Blocking No — crawling allowed
User-agent: *
Disallow:

sitemap.xml No sitemap found

No sitemap found

Adding a sitemap helps search engines discover your pages.

B
TLS Certificate Expiry & Recommendations
38 days until leaf cert expires — 4 issues to address
REVIEW

Certificate validity

38
days left
0d 30d 60d 90d+

Recommended actions

  • Add includeSubDomains to the HSTS directive
  • Add the preload directive and submit to hstspreload.org once max-age + includeSubDomains are in place
  • 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
1 A records, 194 ms lookup
PASS
1 A records, 194 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 76.76.21.123
Info::
Single A record — no DNS redundancy
Multiple A records provide failover if one server goes down.
Info::
No IPv6 (AAAA) records
Info::
2 nameserver(s) configured
Got: cody.ns.cloudflare.com, jean.ns.cloudflare.com
Info::
2 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: 194 ms
Got: 194 ms
A76.76.21.123
AAAA
CNAME
NScody.ns.cloudflare.com, jean.ns.cloudflare.com
MX
10 in1-smtp.messagingengine.com
20 in2-smtp.messagingengine.com
TXT
google-site-verification=3c77ak7h3H3q50wfkn4wWqPB81AwaP11l6UGS_2z2lk
google-site-verification=DHZNw0pjrHLVyiT4ye8vsk-iXzPoEuVgZdrwdbflYnc
google-site-verification=de9MMH-gUcDWFFQD3-tjD2nWdofR3UDSsaafUj9HVpc
v=MCPv1; k=ed25519; p=lLXgJJS2PJ0wSEX4XNtcNbE1A68dg4vZ+WaymedYEbs=
SPF v=spf1 include:spf.messagingengine.com ?all
CAALookup not available with standard resolver
Resolved in 194 ms

Multiple A records provide failover if one server goes down.

Why this matters

Single A record means a single point of failure — if that IP goes down, your site is unreachable until DNS TTL expires.

Learn more

Add multiple A records for round-robin failover, or use a managed DNS provider with health-checked failover (Route 53, Cloudflare, NS1). Short TTL (60-300s) lets clients recover faster on outages.

Source: SRE practice / DNS architecture

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://svelte.dev

https://svelte.dev

68 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://svelte.dev20068 msHTTP/1.1Vercel
A
URL Variants
www/non-www, trailing slash, HTTP→HTTPS
PASS
www/non-www, trailing slash, HTTP→HTTPS
Warning::
HTTP→HTTPS redirect uses 302 instead of 301
Got: 302 temporary redirect Expected: 301 permanent redirect

www / non-www

308https://www.svelte.dev/
200https://svelte.dev/

HTTP → HTTPS

308http://svelte.dev/ https://svelte.dev/

Use 301 (permanent) instead of 302 (temporary)

A+
Domain Intelligence
svelte.dev — via CloudFlare, Inc., 7 years, 2 months old, hosted on AWS
PASS
svelte.dev — via CloudFlare, Inc., 7 years, 2 months old, hosted on AWS
Info::
Domain registered until Feb 28, 2027 (11 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: CloudFlare, Inc.
Info::
Hosting: AWS
Got: AS16509
Domain expiry

196 days

February 28, 2027

SSL certificate

38 days

Issued by Let's Encrypt

Domain age

7 years, 2 months

Registered February 28, 2019

DNSSEC

Not enabled

Protects against DNS spoofing

Hosting

AWS

ASN AS16509

76.76.21.123

Registrar

CloudFlare, Inc.

Lock status unknown 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
Registrar CloudFlare, Inc.
Created February 28, 2019 (7 years, 2 months ago)
Expires February 28, 2027 (11 months)
Last Updated February 3, 2026
Name Servers cody.ns.cloudflare.com, jean.ns.cloudflare.com
DNSSEC Not enabled
Hosting
IP Address 76.76.21.123
ASN AS16509 (AMAZON-02 - Amazon.com, Inc., US)
Provider AWS
Data source: rdap (0.4s)

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

A+
HTTP Probe Timing
Total 81 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
44 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
2 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
9 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
81 ms
Total Time Total request time from DNS lookup through full response.
81 ms

Connection waterfall

DNS Lookup 44 ms TCP Connect 2 ms TLS Handshake 9 ms Server Processing 25 ms Content Transfer 1 ms
A+
CDN & Delivery
Vercel (HIT)
PASS
Vercel (HIT)
Info::
Site is served via Vercel CDN
Got: x-vercel-id: sfo1::6lxnm-1775321043117-a3d8dbf377e4
Info::
CDN cache status: HIT
CDN Detected: Vercel
Provider Vercel Cache Status HIT Evidence x-vercel-id: sfo1::6lxnm-1775321043117-a3d8dbf377e4
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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