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https://bun.sh

Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
87
GRADE
B
FIX
1
REVIEW
1
PASS
7
INFO
0
Probed from Santa Clara, United Stated
200 OK
Checks
9
7 PASS 1 REVIEW 1 FIX
F
IPv6 Readiness
Action
IPv6 records exist but unreachable
FIX
IPv6 records exist but unreachable
Warning::
IPv6 DNS records exist but server is not reachable
Having AAAA records but an unreachable server is worse than no AAAA — clients may experience delays before falling back to IPv4.
Got: 2606:4700:20::681a:58a, 2606:4700:20::681a:48a, 2606:4700:20::ac43:46e2
Info::
IPv6 connection error
Got: dial tcp6 [2606:4700:20::681a:58a]:443: connect: network is unreachable
IPv6 Misconfigured
AAAA Records 2606:4700:20::681a:58a, 2606:4700:20::681a:48a, 2606:4700:20::ac43:46e2 Connection UNREACHABLE

Having AAAA records but an unreachable server is worse than no AAAA — clients may experience delays before falling back to IPv4.

Why this matters

Advertising IPv6 (AAAA records) without a reachable server means IPv6-preferring clients silently fail every connection.

Learn more ▾

Modern browsers prefer IPv6 if AAAA exists (Happy Eyeballs algorithm). If the IPv6 server isn't reachable, browsers fall back to IPv4 — but with seconds of added latency per request. Either fix IPv6 reachability or remove the AAAA records.

Source: RFC 8305 (Happy Eyeballs)

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

Certificate validity

54
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
3 A records, 7 ms lookup
PASS
3 A records, 7 ms lookup
Info::
Resolves to 3 IPv4 address(es)
Got: 172.67.70.226, 104.26.4.138, 104.26.5.138
Info::
Has 3 IPv6 (AAAA) record(s)
Got: 2606:4700:20::681a:58a, 2606:4700:20::681a:48a, 2606:4700:20::ac43:46e2
Info::
2 nameserver(s) configured
Got: hans.ns.cloudflare.com, naomi.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: 7 ms
Got: 7 ms
A172.67.70.226, 104.26.4.138, 104.26.5.138
AAAA2606:4700:20::681a:58a, 2606:4700:20::681a:48a, 2606:4700:20::ac43:46e2
CNAME—
NShans.ns.cloudflare.com, naomi.ns.cloudflare.com
MX
1 aspmx.l.google.com
5 alt1.aspmx.l.google.com
5 alt2.aspmx.l.google.com
10 alt4.aspmx.l.google.com
10 alt3.aspmx.l.google.com
TXT
cursor-domain-verification-5p21cc=8cxGXzcACCGQ8rIilPgJZib1c
google-site-verification=8tTbK_Ha58p_ky7XkbSVJD3E-1Cah_sixJwuoLV7uTo
google-site-verification=V5rdoysBB3bQNxvdbgL0njjkR5ufY_PxfUD6voW2Blo
google-site-verification=g5pTH4JY35JcSqcmMHwCos8L8CQPvG8NQnb1n81fqgA
google-site-verification=hoLJHMr9fqqFedwduPegjN-iEuDDv_dmSO-b9EaECXo
SPF v=spf1 include:spf.efwd.registrar-servers.com include:_spf.google.com ~all
CAALookup not available with standard resolver
Resolved in 7 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://bun.sh

https://bun.sh

93 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://bun.sh20093 msHTTP/1.1cloudflare
A+
Crawlability
robots.txt present, sitemap with 16909 URLs
PASS
robots.txt present, sitemap with 16909 URLs
Info::
robots.txt is present
Got: 40 bytes
Info::
sitemap.xml is present
Info::
sitemap.xml is valid XML
Info::
sitemap.xml contains 16909 entries
Info::
robots.txt does not reference a sitemap
Add a 'Sitemap:' directive to robots.txt so search engines can discover your sitemap.

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 40 B Sitemaps referenced 0 User-agents * Blocking No — crawling allowed
User-agent: *
Disallow: /readme
Allow: /
sitemap.xml 200 OK
Type URL Set URLs 16909 entries Valid XML Yes
Sample URLs:
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.bun.sh/
200https://bun.sh/

Preferred variant: non-www

HTTP → HTTPS

301http://bun.sh/ → https://bun.sh/

Consistent

A+
Domain Intelligence
bun.sh — via MarkMonitor Inc., 4 years, 8 months old, hosted on Cloudflare
PASS
bun.sh — via MarkMonitor Inc., 4 years, 8 months old, hosted on Cloudflare
Info::
Domain registered until Aug 16, 2028 (2 years, 4 months remaining)
Info::
Registrar: MarkMonitor Inc.
Info::
Hosting: Cloudflare
Got: AS13335
Domain expiry

794 days

August 16, 2028

SSL certificate

54 days

Issued by Google Trust Services

Domain age

4 years, 8 months

Registered August 16, 2021

DNSSEC

Status unknown

Protects against DNS spoofing

Hosting

Cloudflare

ASN AS13335

104.26.5.138

Registrar

MarkMonitor Inc.

Lock status unknown 2 NS records
Expiry timeline
Today
+1 year
Domain expiry SSL expiry Danger zone (≤30 days)
Registrar MarkMonitor Inc.
Created August 16, 2021 (4 years, 8 months ago)
Expires August 16, 2028 (2 years, 4 months)
Last Updated March 7, 2026
Name Servers hans.ns.cloudflare.com, naomi.ns.cloudflare.com
Registrant Anthropic PBC
Hosting
IP Address 104.26.5.138
ASN AS13335 (CLOUDFLARENET - Cloudflare, Inc., US)
Provider Cloudflare
Data source: whois (0.4s)
A+
HTTP Probe Timing
Total 123 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
6 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
5 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
11 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
120 ms
Total Time Total request time from DNS lookup through full response.
123 ms

Connection waterfall

DNS Lookup 6 ms TCP Connect 5 ms TLS Handshake 11 ms Server Processing 98 ms Content Transfer 3 ms
A
CDN & Delivery
Cloudflare (DYNAMIC)
PASS
Cloudflare (DYNAMIC)
Info::
Site is served via Cloudflare CDN (edge: SJC)
Got: cf-ray: 9e7274b2eed23117-SJC
Info::
CDN cache status: DYNAMIC
CDN Detected: Cloudflare
Provider Cloudflare Cache Status DYNAMIC Evidence cf-ray: 9e7274b2eed23117-SJC
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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