Technical SEO for IT blogs: canonical URLs, sitemap, structured data, and Core Web Vitals

Technical SEO is a foundation#

Deep technical content matters most, but good content can underperform if metadata is weak, canonical URLs are wrong, sitemap is missing, performance is poor, or multilingual signals are unclear.

Title and description#

Each article should have a unique title and description that accurately describe the problem and the value of reading the page. Avoid keyword stuffing.

Canonical URLs#

Canonical tags identify the preferred URL when similar content can be reached through multiple URLs, tracking parameters, or mirrors.

<link rel="canonical" href="https://example.com/blog/docker-production-image" />

Sitemap, robots, and structured data#

Sitemaps help discovery. Robots.txt can discourage crawling of admin routes, but it is not security. Article structured data helps machines understand title, author, publish time, modification time, and images. It must match visible content.

Core Web Vitals#

• LCP: optimize large images, preload critical resources, and reduce blocking work.
• INP: reduce unnecessary JavaScript and expensive event handlers.
• CLS: reserve image dimensions and avoid late layout shifts.

Multilingual content#

If pages have full English and Vietnamese versions, route-level i18n with /en/..., /vi/..., and hreflang is best for SEO. For a client-side language switch, make sure the visible UI and article content match the selected language.

Primary references#

• Google Search Central: Canonicalization
• Google Search Central: Localized versions
• web.dev: Core Web Vitals