1. Rendering Strategy Matters
How your JavaScript framework renders content affects whether search engines can index it.
Client-side rendering (CSR): Search engines can execute JavaScript, but it's slower and less reliable. Not ideal for content-heavy sites that depend on organic traffic.
Server-side rendering (SSR): HTML is rendered on the server, so search engines get fully-formed content immediately. Better for SEO but adds server complexity.
Static site generation (SSG): Pre-render pages at build time. Best performance and SEO, but only works if content doesn't change frequently.
For most applications that care about SEO, SSR or SSG with incremental regeneration (Next.js ISR, for example) is the right choice.
2. Core Web Vitals Are Ranking Factors
Google uses page experience signals as ranking factors. The most important are Core Web Vitals:
Optimize these with: code splitting to reduce bundle size, lazy loading images below the fold, proper image dimensions to prevent layout shifts, prefetching critical resources, and using a CDN for static assets.
- Largest Contentful Paint (LCP): How quickly the main content loads (aim for under 2.5s)
- Cumulative Layout Shift (CLS): How much the page layout shifts during load (aim for under 0.1)
- Interaction to Next Paint (INP): How quickly the page responds to interactions (aim for under 200ms)
3. Crawl Budget and Site Structure
Search engines allocate a limited crawl budget to each site. Don't waste it on unimportant pages.
Use robots.txt to block pages that don't need indexing (admin pages, search result pages, thank-you pages). Create an XML sitemap with your important pages, prioritized by importance. Fix redirect chains—every redirect wastes crawl budget. Implement proper canonical tags to avoid duplicate content issues.
4. Structured Data (Schema.org)
Structured data helps search engines understand your content and can enable rich results in search.
Implement JSON-LD schema for: Organization, Article/BlogPosting, Product, FAQ, BreadcrumbList, and any other relevant types for your content.
Test your schema with Google's Rich Results Test tool. This isn't just for looking good in search results—it helps search engines understand content relationships and improve rankings.
5. URL Structure and Internal Linking
Clean, logical URL structure helps both users and search engines understand your site.
Use descriptive URLs (/blog/technical-seo-guide, not /post?id=123). Keep URLs short and readable. Implement breadcrumb navigation. Build smart internal linking—link from high-authority pages to important pages. Use descriptive anchor text.
6. Mobile-First is Mandatory
Google indexes the mobile version of your site first. If your mobile experience is broken, your rankings suffer.
Ensure responsive design works correctly. Test on real devices, not just Chrome DevTools. Watch for tap target sizes (buttons should be at least 48x48px). Avoid intrusive interstitials on mobile.
7. HTTPS is Non-Negotiable
HTTPS is a ranking signal. Sites without HTTPS are marked as 'Not Secure' in browsers.
Use HTTPS everywhere. Implement HSTS headers. Ensure mixed content issues are resolved. Redirect HTTP to HTTPS with 301 redirects.
Common Developer Mistakes
Blocking search engines with robots.txt in production (yes, this happens). Not implementing proper redirects when URLs change. Loading all JavaScript upfront instead of code-splitting. Not setting proper cache headers. Forgetting to update meta descriptions and titles when content changes.
The good news: these are all fixable with code, not content marketing skills.
Conclusion
Technical SEO isn't mysterious—it's about making your site fast, crawlable, and understandable to search engines. Most technical SEO work is just good engineering: fast page loads, clean URLs, proper HTTP headers, and semantic HTML. If you build a technically sound site, you've solved 80% of SEO before content even matters.