Technical SEO guides, no filler
Reference content, very extensive and in depth, for anyone who wants to understand how SEO actually works under the hood: crawling, rendering, canonicalization, structured data, speed and redirects. Different from the blog: no timely articles here, just technical manuals that don't go stale.
Crawling and indexing: the complete technical guide
How Googlebot and other crawlers decide which pages to visit, how often, and which ones make it into the index: crawl budget, robots.txt, sitemaps, server log analysis and the mistakes that waste the most crawl budget.
</>Technical Guide Rendering & JavaScriptJavaScript and SEO: a technical rendering guide
Why JavaScript-generated content causes the most indexing problems, how Google's two-phase rendering actually works, and how to choose between SSR, SSG and hydration depending on the project.
</>Technical Guide Architecture & ContentCanonicalization and duplicate content: a technical guide
How to tell Google which is the "official" version of a page when several URLs share identical or near-identical content, and the configuration mistakes that confuse the canonicalization algorithm the most.
</>Technical Guide Architecture & ContentStructured data and Schema.org: a technical implementation guide
How Schema.org markup actually works, why JSON-LD is the recommended format, and how to implement the types that generate the most rich results without the mistakes that make Google ignore them.
</>Technical Guide Performance & Core Web VitalsCore Web Vitals: an in-depth technical guide
What each Core Web Vital (LCP, INP and CLS) actually measures, how their thresholds are calculated, and the concrete technical causes, not generic advice, behind a site failing each of the three metrics.
</>Technical Guide Crawling & IndexingRedirects and HTTP status codes: a technical guide
Which HTTP status code to use in each real situation (301, 302, 307, 410...), how to avoid redirect chains and loops, and why the wrong status code can cost a URL its accumulated ranking.
</>Technical Guide Performance & Core Web VitalsTechnical image optimization for SEO
Which format to use in each case (WebP, AVIF, JPEG), how to serve the right size to each device with srcset and picture, and why badly applied lazy loading can hurt LCP instead of improving it.
</>Technical Guide Architecture & ContentWeb architecture and internal linking: a technical guide
How to structure a site into topical silos, how many clicks there should be at most to reach any page, and why internal linking distributes authority in a way you can directly control.
</>Technical Guide Infrastructure & SecurityHTTPS and security as a technical SEO factor
Why HTTPS stopped being optional, what mixed content is and how to spot it, and how a hack or an expired certificate can knock your site out of Google's index within hours.
</>Technical Guide International SEOhreflang: the complete technical guide to international SEO
How the hreflang tag actually works, why it must always be bidirectional, and the implementation mistakes that make Google ignore it entirely without any visible warning.
</>Technical Guide Audits & MigrationsWebsite migrations without losing rankings: a technical guide
The technical process for changing domains, moving to HTTPS or switching CMS without losing accumulated organic traffic: URL mapping, redirects, and why the order of the steps matters as much as the steps themselves.
</>Technical Guide Crawling & IndexingMobile-first indexing: what actually changes technically
Why Google uses your site's mobile version to index and rank it, even for a desktop user, and the configuration mistakes that make the mobile version show less content than desktop without anyone noticing.
</>Technical Guide Performance & Core Web VitalsHTTP caching and CDN: a technical performance guide
What each cache header actually controls (Cache-Control, ETag, Expires), how a CDN works to reduce latency, and why overly aggressive caching can make users see outdated content.
</>Technical Guide Architecture & ContentTechnical pagination and infinite scroll: an SEO guide
Why rel=next/prev no longer exists as a Google signal, how to keep infinite scroll from hiding content from crawlers, and when to consolidate a paginated series with canonical instead of leaving it indexable page by page.
</>Technical Guide Audits & MigrationsTechnical audit methodology using crawlers
How to structure a technical SEO audit from start to finish with a Screaming Frog-style crawling tool: what to configure before launching the crawl, which reports to check first, and how to prioritize findings by real impact.
</>Technical Guide Infrastructure & SecurityCompromised security and index recovery: a technical guide
How to technically detect a site has been compromised before Google does, the most common injection types (spam content, hidden redirects, cloaking), and the exact process for recovering the index after a cleanup.
</>Technical Guide Crawling & IndexingAdvanced robots.txt: directives, wildcards and real-world mistakes
How crawlers actually interpret the * and $ wildcards, which rule wins when several could match the same URL, why Google ignores Crawl-delay while other bots respect it, and the configuration mistakes that show up most often in real audits.
</>Technical Guide Audits & MigrationsServer log analysis for technical SEO
How to read Apache and Nginx access logs to see Google's real crawling activity, how to verify with reverse DNS that a bot is genuinely Googlebot and not an impostor, and which crawl patterns, errors and orphan pages are worth looking for before they become an indexing problem.
</>Technical Guide Performance & Core Web VitalsServer speed and TTFB: what hosting actually controls
What Time to First Byte actually measures, what happens in each phase between the request and the server's first response, how hosting type, server location, and PHP and database configuration affect it, and the concrete numbers that separate a good TTFB from an acceptable or poor one.
</>Technical Guide Performance & Core Web VitalsHTTP/2, HTTP/3 and QUIC: the real technical impact on SEO
What actually changed between HTTP/1.1, HTTP/2 and HTTP/3: multiplexing, header compression, the server push feature that got abandoned, and QUIC over UDP with connection migration. How to check which protocol a site actually serves and how much this really weighs in rankings, without overselling it.
</>Technical Guide Infrastructure & SecurityDNS and technical SEO: propagation, TTL and how they affect crawling
How DNS resolution fits into the crawling process, the real trade-off between a low and a high TTL, what happens to crawling during a nameserver migration, the risks of a badly configured DNSSEC setup, and how CDN anycast changes the very idea of "where" a server actually is.
</>Technical Guide Audits & MigrationsTechnical speed auditing with Lighthouse and PageSpeed Insights
How Lighthouse's lab-data scoring actually works versus PageSpeed Insights' field data (the CrUX report), how to read a Lighthouse report without falling for false positives, and how to automate Lighthouse in CI to catch regressions before they ship.
</>Technical Guide Crawling & IndexingCrawl traps and infinite URL spaces: how to detect and fix them
Endless calendars, combinatorial faceted navigation, session-ID parameters and relative-link bugs that generate ever-deeper nested paths: how to detect infinite URL spaces that sink crawl budget with a crawler, and how to close each pattern for good.
</>Technical Guide Rendering & JavaScriptTechnical SEO for headless and JAMstack sites
What actually changes for technical SEO when content lives in a headless CMS and the site ships as JAMstack: why most rendering problems disappear, but preview-environment leaks, edge-layer redirect management, and broken cross-source canonicals show up instead.
</>Technical Guide Infrastructure & SecurityUptime and server availability: the real impact on crawling
What Googlebot technically does when it hits downtime or intermittent 5xx errors, how the crawl-rate algorithm reacts and how long it takes to recover trust, and which hosting-level factors (shared-host contention, real monitoring) determine a site's reliability.
</>Technical Guide Audits & MigrationsTechnical launch checklist: from staging to production without losing SEO
The concrete list of checks before and after taking a site from staging to production: removing the staging noindex/robots block, verifying redirects before the DNS cutover, sitemap and canonical pointing to production, SSL/HSTS configured correctly, and the first-48-hours monitoring routine.
</>Technical Guide Infrastructure & SecuritySSL/TLS: technical configuration and the mistakes that hurt SEO
Beyond "having HTTPS": how to validate the certificate chain, why TLS 1.0 and 1.1 need to be retired, how to configure HSTS and its preload list without locking yourself out, and how to audit mixed content across an entire site.
</>Technical Guide Rendering & JavaScriptRendering for SEO: SSR, SSG, CSR and prerendering
An architecture-level comparison of server-side rendering, static site generation, client-side rendering and prerendering as a stopgap: the concrete tradeoffs of each in TTFB, interactivity, build complexity and hosting cost, and when each one makes sense.
</>Technical Guide Audits & MigrationsHosting migration without losing SEO
The specific technical process for switching hosting providers or server IP without touching the domain: lowering the DNS TTL in advance, keeping both servers in sync during the transition window, verifying DNS propagation, and what to check in the first hours after cutover.
</>Technical Guide Crawling & IndexingAdvanced meta robots: noindex, nofollow, none, noarchive, nosnippet, max-snippet
A complete reference of meta robots directives beyond noindex/nofollow: none as a shortcut, noarchive and its relevance today, nosnippet, fine-grained control with max-snippet/max-image-preview/max-video-preview, and what wins when meta robots and X-Robots-Tag contradict each other.
</>Technical Guide Crawling & IndexingIndex sitemaps for large sites: images, video and news
Beyond the basic sitemap: how to structure a sitemap index once you exceed the 50,000-URL limit, the required fields for image, video and news sitemaps, splitting strategies by content type, date or section, and how to read the gap between "submitted" and "indexed" in Search Console.
</>Technical Guide Architecture & ContentURL structure and technical normalization: case, trailing slashes and parameters
Why case, trailing slashes, query parameter order, or mixing www and https produce technically distinct URLs for the same content, and how to normalize them with canonical tags, 301 redirects and server rules before they turn into duplicates competing against each other.
</>Technical Guide Rendering & JavaScriptTechnical SEO for SPAs: client-side routing and indexability
How routing works in a single-page application (React Router, Vue Router), why switching "screens" without a browser reload creates URLs a crawler may never see, and how to configure the History API, real links and loading states so every view is a genuinely indexable URL.
</>Technical Guide Architecture & ContentWeb accessibility (WCAG) and its technical relationship with SEO
Semantic HTML, alt text, heading hierarchy and keyboard focus aren't just accessibility requirements: they're signals a crawler processes the same way a screen reader does. Which accessibility practices have a direct technical effect on how Google understands a page.
</>Technical Guide Performance & Core Web VitalsThird-party scripts and Core Web Vitals: the technical cost of tags, pixels and widgets
Every tag manager, ad pixel, live chat or reviews widget adds JavaScript you don't directly control and that competes for the same main thread as your page's content. How to measure its real cost on INP and LCP, and the techniques (lazy loading, facades, task splitting) for keeping them without sacrificing performance.
</>Technical Guide International SEOccTLD, subdomain or subfolder: the technical decision for international and multi-brand SEO
Three technically distinct ways to structure a site for multiple countries or brands (a dedicated per-country domain, a subdomain or a subfolder), how much domain authority each inherits, how it affects hreflang and hosting management, and which real-world criteria, not just SEO, should tip the decision in each case.