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Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
79
GRADE
C
FIX
1
REVIEW
4
PASS
4
INFO
0
Probed from Madrid, Spain
301 Moved Permanently
Checks
9
4 PASS 4 REVIEW 1 FIX
D
CDN & Delivery
Action
No CDN detected
FIX
No CDN detected
Warning::
No CDN detected
A CDN can significantly improve load times for users around the world by caching content at edge nodes closer to them.
No CDN detected

Consider using a CDN to improve global delivery speed and reduce origin load.

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

C
Crawlability
Action
robots.txt present, sitemap with 0 URLs
REVIEW
robots.txt present, sitemap with 0 URLs
Info::
robots.txt is present
Got: 10240 bytes
Info::
sitemap.xml is present
Warning::
sitemap.xml contains invalid XML
Search engines may not be able to parse the sitemap. Fix XML validation errors.
Warning::
sitemap.xml is empty — no URLs found
An empty sitemap provides no value. Add <url> entries for your pages.
Info::
robots.txt does not reference a sitemap
Add a 'Sitemap:' directive to robots.txt so search engines can discover your sitemap.

Search engines may not be able to parse the sitemap. Fix XML validation errors.

Why this matters

An unparseable sitemap is silently ignored by Google — the URLs it advertises are never queued for crawl.

Learn more ▾

Google's sitemap parser is strict about XML validity. A single unescaped `&` or unclosed tag invalidates the whole file. Run your sitemap through a validator (Search Console's Sitemaps report flags it) and fix the offending entry. Most generators escape correctly; mistakes usually come from manually-written entries.

Source: sitemaps.org / Google Search Central

An empty sitemap provides no value. Add <url> entries for your pages.

Why this matters

An empty sitemap signals 'no content to index' to Google — actively harmful versus having no sitemap at all.

Learn more ▾

Google compares URLs in the sitemap against URLs it has crawled. An empty sitemap on a site with thousands of pages signals abandonment. Either populate it correctly (most CMSes auto-generate) or delete the file and let Google crawl normally.

Source: Google Search Central / sitemaps.org

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 10240 B Sitemaps referenced 0 User-agents Blocking No — crawling allowed
<!DOCTYPE html>
<html lang="en">
  <head id="htmx-head">
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
    
    <meta name="description" content="OCaml is a general-purpose, industrial-strength programming language with an emphasis on expressiveness and safety.">
    
    <meta name="twitter:title" content="Welcome to a World of OCaml">
    
    <meta name="twitter:description" content="OCaml is a general-purpose, industrial-strength programming language with an emphasis on expressiveness and safety.">
    
    <meta name="twitter:image" content="https://ocaml.org/_/MWIyY2ZmMWM5YzdkYWNmYWI4NGQ0MDBjOGFiZTYxOTg/ocaml_org_social_media.png">
    <meta property="og:site_name" content="OCaml">
    <meta property="og:type" content="object">
    <meta property="og:title" content="Welcome to a World of OCaml">
    
    <meta property="og:description" content="OCaml is a general-purpose, industrial-strength programming language with an emphasis on expressiveness and safety.">
    
    <meta name="og:image" content="https://ocaml.org/_/MWIyY2ZmMWM5YzdkYWNmYWI4NGQ0MDBjOGFiZTYxOTg/ocaml_org_social_media.png">
    <meta name="theme-color" content="#fff" >
    <meta name="color-scheme" content="white">
    
    <meta name="ahrefs-site-verification" content="6ff715b377cdcd566334b44ae8888791189ce24640c8a403eacdc3bcbaa9449b">
    <link rel="canonical" href="https://ocaml.org">
    
    <link rel="icon" type="image/x-icon" href="/_/ZDJmMjgzN2NkZmJlMzgxNGQxMTMxNGVlMzk1NzZkN2I/favicon.ico">
    <link rel="manifest" href="/manifest.json">
    
    <link rel="stylesheet" href="/_/ZDBlYzBjZTdmOGJmMGE2YmY3YjNmOGNkNGZkMmQ5ZWU/css/main.css">
    
    <link rel="stylesheet" href="/_/NmFjYjY5ZmIxYWRhMWQxMTQxODM4ZDEwYTgwMDcwNmI/vendors/font-files/inter.css">
    <link rel="stylesheet" href="/_/YjM3OGY4YzIwN2E2ZmUxZTczOWVkNDQwZWRhMDU0MGM/vendors/font-files/roboto-mono.css">
    <script defer src="/_/OWYyZDQyZjg4MTFlNWEzZjE4ZGY0YWM0OTU1NGEzYTI/vendors/alpine-clipboard.js"></script>
    <script defer src="/_/NGI1NjQzZjdkODY0MTY2MmViNThhM2VlZTYwMDk3NTI/vendors/alpine.min.js"></script>
    <script defer src="/_/YTNhODI2Yzg0Yzk4M2ZiNDcxYmRiYzdhY2FiN2Y0OWQ/vendors/htmx.min.js"></script>
    <script defer data-domain="ocaml.org" src="https://plausible.ci.dev/js/script.js"></script>
    
    <link rel="stylesheet" href="/_/YmM5NjJlN2E4YzVkMDBmMDQ2ODEwNTQyNTBkNzE2MmM/vendors/swiper-bundle.min.css">
    <link rel="alternate" type="application/rss+xml" title="OCaml Planet Feed" href="/planet.xml">
    <script src="/_/ZDJiMGNkNGMzMjBlYjNmZGUxNTMxOTAyNjA0MDU2N2Q/vendors/swiper-bundle.min.js"></script>
    
    <link rel="search" href="/opensearch.xml" type="application/opensearchdescription+xml" title="OCaml">
    <title>Welcome to a World of OCaml</title>
  </head>

  <body>
    <script>
      if (localStorage.theme === 'dark' || (!('theme' in localStorage) && window.matchMedia && window.matchMedia('(prefers-color-scheme: dark)').matches)) {
        document.body.classList.add("dark");
      } else {
        document.body.classList.remove("dark");
      }
    </script>
    

    <header
  class="h-20 flex items-center bg-sand dark:bg-dark-background_navigation"
  x-data="{ open: false }">
  <nav class="container-fluid wide header flex justify-between items-center gap-5 xl:gap-8">
    <ul class="order-0 space space-x-5 xl:space-x-8 items-center flex text-content font-medium dark:text-title dark:text-opacity-60 dark:font-semibold">
      <li style="width:132px">
        <a href="/" class="block pb-2">
          <img src="/_/MDBjN2M4YjIxY2Y1YWExZWE3Njk4M2FiZTg1NWZjNTM/logo-with-name.svg" width="132" alt="OCaml logo" class="dark:hidden">
          <img src="/_/MTE3YWE5YzJlZmExNmYyMmI3ZmEwYjliMDEwNDBkMDY/logo-with-name-white.svg" width="132" alt="OCaml logo" class="hidden dark:inline">
        </a>
      </li>
    </ul>
    <ul class="order-2 hidden lg:flex items-center">
      <li>
        <form
           x-data="{ row: null, col: 0, max: 0, total: 0 }"
       @submit="if (row !== null) { window.location = document.getElementById('package-autocomplete-'+row+'-'+col).getAttribute('href'); $event.stopPropagation(); $event.preventDefault(); return false }" 
          action="/packages/search" method="GET">
          <div class="dropdown-container flex items-center justify-center h-10 rounded-md focus-within:outline-primary_25 dark:focus-within:outline-dark-primary_40 focus-within:outline focus-within:outline-2 lg:w-56 xl:w-80" tabindex="0">
  <label for="q" class="sr-only">Search OCaml packages</label>
  <input
      type="search"
      name="q"
      placeholder="Search OCaml packages"
      @keydown.escape="$event.target.blur()"
      class="bg-white dark:bg-dark-card text-title dark:text-dark-title h-full w-full font-normal focus:border-primary dark:focus:border-dark-primary focus:ring-0 border-primary dark:border-dark-primary rounded-md rounded-r-none px-3 py-1 placeholder-text-content dark:placeholder:text-dark-content appearance-none focus:outline-none"
      @keydown.stop   @keyup.down="if (row === null) { row = 0; col = 0; } else { row +=1; if (row > max) { row = max } }"
        @keyup.up="if (row !== null) { row -=1; if (row < 0) { row = null } }"
        @keyup.right="if (col < 1) col++"
        @keyup.left="if (col >= 1) col--"
        :aria-activedescendant="row !== null ? 'package-autocomplete-'+row+'-'+col : null"

        hx-get="/packages/autocomplete"
        hx-params="q"
        hx-trigger="keyup changed, search"
        hx-target="#header-search-results"
        hx-indicator="#header-search-indicator"
        autocomplete="off"
        
  >
  
  <button
      aria-label="search"
      class="h-full flex items-center justify-center rounded-r-md bg-primary dark:bg-dark-primary text-white dark:text-dark-white px-4"
      type="submit"
  ><svg xmlns="http://www.w3.org/2000/svg" class="w-6 h-6" fill="none" viewBox="0 0 24 24" stroke="currentColor" aria-hidden="true">
  <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M21 21l-6-6m2-5a7 7 0 11-14 0 7 7 0 0114 0z" />
</svg>

</button>

  <div class="dropdown w-full lg:w-[32rem] xl:w-[32rem] z-10 absolute rounded-md mt-12 shadow-2xl top-1 p-2 bg-background dark:bg-dark-background shadow-3xl dark:outline dark:outline-1 dark:outline-primary">
    <div id="header-search-results" aria-live="polite"></div>
<a class="flex py-2 px-2 mx-2 gap-4 hover:bg-primary_nav_block_hover_10 dark:hover:bg-dark-primary_nav_block_hover_10 font-normal rounded-md text-primary dark:text-dark-primary" href="/api">
  Standard Library API
  <svg xmlns="http://www.w3.org/2000/svg" class="w-6 h-6" fill="none" viewBox="0 0 24 24" stroke="currentColor" aria-hidden="true">
  <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M10 6H6a2 2 0 00-2 2v10a2 2 0 002 2h10a2 2 0 002-2v-4M14 4h6m0 0v6m0-6L10 14"></path>
</svg>


</a>

</div>

</div>


        </form>
      </li>
    </ul>
    <ul class="order-1 mr-auto items-center hidden lg:flex font-medium dark:text-white dark:text-opacity-60 dark:font-semibold">
      
      <li><a href="/docs" class="block font-normal py-3 mg:py-4 px-1 lg:px-3 hover:text-primary dark:hover:text-dark-primary text-title dark:text-dark-title">Learn</a>


</li>
      
      <li><a href="/tools" class="block font-normal py-3 mg:py-4 px-1 lg:px-3 hover:text-primary dark:hover:text-dark-primary text-title dark:text-dark-title">Tools</a>


</li>
      
      <li><a href="/packages" class="block font-normal py-3 mg:py-4 px-1 lg:px-3 hover:text-primary dark:hover:text-dark-primary text-title dark:text-dark-title">Packages</a>


</li>
      
      <li><a href="/community" class="block font-normal py-3 mg:py-4 px-1 lg:px-3 hover:text-primary dark:hover:text-dark-primary text-title dark:text-dark-title">Community</a>


</li>
      
      <li><a href="/changelog" class="block font-normal py-3 mg:py-4 px-1 lg:px-3 hover:text-primary dark:hover:text-dark-primary text-title dark:text-dark-title">News</a>


</li>
      
      <li><a href="/play" class="block font-normal py-3 mg:py-4 px-1 lg:px-3 hover:text-primary dark:hover:text-dark-primary text-title dark:text-dark-title">Play</a>


</li>
      
    </ul>
    
    <ul class="order-3 hidden lg:flex items-center">
      <li><a href="/docs/get-started" class="border border-primary dark:border-dark-primary text-primary dark:text-dark-primary font-bold py-2.5 px-7 whitespace-nowrap rounded">Get Started</a></li>
    </ul>
    
    <ul class="order-1 lg:hidden flex items-center">
      <li
        class="h-12 w-12 hover:bg-primary_25 dark:hover:bg-primary_20 flex items-center justify-center rounded-full text-content dark:text-dark-title">
        <button aria-label="open menu" @click="open = ! open">
          <svg xmlns="http://www.w3.org/2000/svg" class="h-8 w-8" fill="none" viewBox="0 0 24 24" stroke="currentColor" aria-hidden="true">
  <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M4 6h16M4 10h16M4 14h16M4 18h16" />
</svg>


        </button>
      </li>
    </ul>
  </nav>

  <div class="bg-black fixed w-full h-full left-0 top-0 opacity-60 z-40" x-show='open' x-cloak></div>

  <nav class="z-50 h-full fixed right-0 top-0 max-w-full w-96 bg-background dark:bg-dark-background shadow-lg" x-show="open" x-cloak
    @click.away="open = false" x-transition:enter="transition duration-200 ease-out"
    x-transition:enter-start="translate-x-full" x-transition:leave="transition duration-100 ease-in"
    x-transition:leave-end="translate-x-full">
    <ul class="text-content p-6 font-semibold">
      <li class="flex justify-between items-center">
        <a href="/">
          <img src="/_/MDBjN2M4YjIxY2Y1YWExZWE3Njk4M2FiZTg1NWZjNTM/logo-with-name.svg" width="132" alt="OCaml logo" class="dark:hidden">
          <img src="/_/MTE3YWE5YzJlZmExNmYyMmI3ZmEwYjliMDEwNDBkMDY/logo-with-name-white.svg" width="132" alt="OCaml logo" class="hidden dark:inline">
        </a>

        <div class=""
          x-on:click="open = false">
          <button aria-label="close" class="text-content dark:text-dark-title">
            <svg xmlns="http://www.w3.org/2000/svg" class="h-8 w-8" fill="none
sitemap.xml 200 OK
Type URL Set URLs 0 entries Valid XML No
B
URL Variants
www/non-www, trailing slash, HTTP→HTTPS
REVIEW
www/non-www, trailing slash, HTTP→HTTPS
Critical::
Both www and non-www versions serve content
Got: Both variants return 200 Expected: One variant 301-redirects to the other
Info::
HTTP correctly 301-redirects to HTTPS

www / non-www

200https://www.ocaml.org/
200https://ocaml.org/

Inconsistent — duplicate content risk

HTTP → HTTPS

301http://www.ocaml.org/ → https://ocaml.org

Consistent

B
TLS Certificate Expiry & Recommendations
62 days until leaf cert expires — 3 issues to address
REVIEW

Certificate validity

62
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
1 A records, 37 ms lookup
PASS
1 A records, 37 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 51.159.83.169
Info::
Single A record — no DNS redundancy
Multiple A records provide failover if one server goes down.
Info::
No IPv6 (AAAA) records
Info::
No NS records found
Info::
No MX records — email not configured via DNS
Info::
CAA records not checked
CAA record lookup requires a specialized DNS resolver. This check will be available in a future update.
Info::
No SPF record found in TXT records
SPF helps prevent email spoofing. Add a TXT record starting with 'v=spf1'.
Info::
DNS resolution time: 37 ms
Got: 37 ms
A51.159.83.169
AAAA—
CNAME—
NS—
MX—
TXT—
CAALookup not available with standard resolver
Resolved in 37 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.

SPF helps prevent email spoofing. Add a TXT record starting with 'v=spf1'.

Why this matters

Without SPF, receiving servers can't validate sending IPs — your domain is easier to spoof in phishing.

Learn more ▾

SPF complements DMARC. Both should be published. SPF records list authorized sending IPs (e.g., `v=spf1 include:_spf.google.com ~all` for Google Workspace). After publishing, verify in Google Postmaster Tools or mxtoolbox.

Source: RFC 7208 (SPF)

A
Redirect Chain
1 redirect(s), 142 ms total
PASS
1 redirect(s), 142 ms total
Info::
Single redirect
Got: https://www.ocaml.org → https://ocaml.org (301)
Info::
WWW normalization redirect

https://www.ocaml.org

54 ms · HTTP/1.1

301

https://ocaml.org

88 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://www.ocaml.org30154 msHTTP/1.1Varnish
2https://ocaml.org20088 msHTTP/1.1

See the visual redirect chain in the HTTP Probe tab →

A+
Domain Intelligence
ocaml.org — via Gandi SAS, 26 years, 3 months old, hosted on Online SAS, FR
PASS
ocaml.org — via Gandi SAS, 26 years, 3 months old, hosted on Online SAS, FR
Info::
Domain registered until May 23, 2027 (1 years, 1 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: Gandi SAS
Info::
Hosting: Online SAS, FR
Got: AS12876
Domain expiry

314 days

May 23, 2027

SSL certificate

62 days

Issued by Let's Encrypt

Domain age

26 years, 3 months

Registered May 23, 2000

DNSSEC

Not enabled

Protects against DNS spoofing

Hosting

Online SAS, FR

ASN AS12876

51.159.83.169

Registrar

Gandi SAS

Lock status unknown 3 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 Gandi SAS
Created May 23, 2000 (26 years, 3 months ago)
Expires May 23, 2027 (1 years, 1 months)
Last Updated March 29, 2026
Name Servers ns-124-c.gandi.net, ns-164-b.gandi.net, ns-238-a.gandi.net
DNSSEC Not enabled
Hosting
IP Address 51.159.83.169
ASN AS12876 (Online SAS, FR)
Provider Online SAS, FR
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 89 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
37 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
17 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
19 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
89 ms
Total Time Total request time from DNS lookup through full response.
89 ms

Connection waterfall

DNS Lookup 37 ms TCP Connect 17 ms TLS Handshake 19 ms Server Processing 17 ms Content Transfer 0 ms
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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