by The Computing Australia Group | Technical SEO for Developers:
Build Search-Friendly Websites
How to Build Search-Friendly, High-Performing Websites
Search engine optimisation (SEO) is often seen as “someone else’s job” – usually marketing. Many developers assume SEO is about keywords and blog posts, not code and architecture. Others feel that SEO is vague, subjective, or gets in the way of clean engineering.
In reality, modern SEO is deeply technical.
Search engines increasingly reward sites that are fast, secure, accessible, and easy to crawl – all of which sit firmly in the developer’s domain. Your stack, your markup, and your deployment choices can make or break organic performance long before a single keyword is written.
This guide, created with input from SEO specialists and developers, is designed to help you:
- Understand what parts of SEO are in your control
- Build sites that search engines can crawl, index and rank effectively
- Collaborate better with marketers and content teams
- Integrate SEO checks into your usual dev workflow
Whether you’re building a new site, refactoring an application, or maintaining a legacy codebase, this guide will help you use your developer skills to drive better SEO outcomes.
1. SEO Fundamentals for Developers
What is SEO (from a developer’s perspective)?
Search Engine Optimisation (SEO) is the process of helping search engines:
1. Discover your pages (crawling)
2. Understand your content and its context (rendering & indexing)
3. Evaluate the quality and relevance of your pages (ranking)
Marketers tend to focus on keywords, messaging and content strategy. Developers control the “plumbing” that makes all of that discoverable:
- How URLs are structured
- Whether pages are crawlable and indexable
- How quickly pages load on different devices
- How JavaScript is rendered
- How internal links and navigation are implemented
- Whether structured data is present and correct
When developers and marketers work together, SEO becomes much more powerful – and much less painful.
2. Technical SEO Foundations
Technical SEO is where developers add the most value. Think of it as ensuring your site is easy for search engines to crawl, render and index.
2.1 Crawlability & Indexability
If a page can’t be crawled, it can’t rank. If it can be crawled but not indexed, it also can’t rank.
Key elements you control:
Robots.txt
- Use robots.txt to control where crawlers are allowed to go.
- Block only what you truly don’t want crawled (admin areas, internal tools, test environments, etc.).
- Avoid accidentally blocking entire sections like /blog/ or critical CSS/JS files.
Example:
User-agent: *
Disallow: /admin/
Disallow: /cart/
Allow: /
Sitemap: https://www.example.com/sitemap.xml
Meta Robots & X-Robots-Tag
- Avoid setting noindex on templates that power key sections.
HTTP Status Codes
- Use robots.txt to control where crawlers are allowed to go.
- Block only what you truly don’t want crawled (admin areas, internal tools, test environments, etc.).
- Avoid accidentally blocking entire sections like /blog/ or critical CSS/JS files.
Canonical Tags
If multiple URLs can display similar or identical content (e.g. tracking parameters, filters), use canonical tags:
This helps consolidate ranking signals and prevents duplicate content issues.
2.2 XML Sitemaps
XML sitemaps act as a roadmap for search engines.
As a developer, you can:
- Generate sitemaps dynamically (e.g. from your database or CMS)
- Include only indexable URLs that return 200
- Split sitemaps for large sites (e.g. /sitemap-posts.xml, /sitemap-products.xml)
- Reference all sitemaps from an index file and list that in robots.txt
Example snippet from a sitemap:
<url>
<loc>https://www.example.com/blog/seo-guide-for-developers</loc>
<lastmod>2025-11-01</lastmod>
<changefreq>monthly</changefreq>
<priority>0.8</priority>
</url>
2.3 URL Structure & Site Architecture
A clean, logical URL structure helps both users and search engines.
Best practices:
-
Keep URLs readable and descriptive:
https://www.example.com/web-development/seo-guide-for-developers - Use hyphens (-) instead of underscores or spaces.
- Avoid unnecessary parameters in core content URLs.
- Decide on a trailing slash convention (/blog/ vs /blog) and keep it consistent.
- Use lowercase letters to avoid duplication (/Blog vs /blog).
On the architecture side:
- Create a clear hierarchy:
- Home → Category → Subcategory → Detail Page
- Implement breadcrumb navigation to help users and bots understand where they are.
Example breadcrumb markup:
<nav aria-label=”Breadcrumb”>
<ol>
<li><a href=”/”>Home</a></li>
<li><a href=”/web-development/”>Web Development</a></li>
<li aria-current=”page”>SEO Guide for Developers</li>
</ol>
</nav>
2.4 HTTPS, Security & Trust
Search engines favour secure websites because users do.
- Install and renew SSL certificates and redirect all HTTP traffic to HTTPS using 301 redirects.
- Fix mixed-content issues (HTTP resources on HTTPS pages).
- Implement security headers where appropriate (HSTS, X-Content-Type-Options, etc.).
- Ensure all internal links and canonical tags use HTTPS versions of your URLs.
Consistent, secure URLs also prevent diluted ranking signals.
3. On-Page SEO: Implementing Content in Code
On-page SEO isn’t just about words; it’s about how those words are structured in your markup.
3.1 Title Tags
The <title> tag is one of the strongest on-page SEO signals.
Guidelines:
- Keep titles around 50–60 characters so they don’t truncate too much.
- Include the primary keyword and brand (where relevant).
- Make titles unique for every indexable page.
- Avoid dynamically generating identical titles across a large number of pages.
Example:
<title>The SEO Guide for Developers | Example Agency</title>
On large sites, work with marketers to define title templates for categories, products, or articles.
3.2 Meta Descriptions
Meta descriptions influence click-through rate, even though they’re not a direct ranking factor.
- Aim for 120–160 characters.
- Summarise the page value clearly.
- Include relevant keywords naturally.
- Keep descriptions unique; avoid using the same one across hundreds of pages.
Example:
<meta name=”description” content=”Learn how developers can improve SEO with better code, site architecture, Core Web Vitals, and collaboration with marketing teams.” />
If your content team writes the copy, your job is to integrate it correctly and ensure it’s not stripped out or overwritten by templates.
3.3 Heading Structure & Semantic HTML
Headings and semantic tags help search engines understand page structure, and they improve accessibility.
Best practices:
- Use one <h1> per page for the main heading.
- Use <h2>, <h3>, etc. to structure sections logically.
- Use HTML5 semantic tags like <main>, <article>, <section>, <aside>, <nav>, and <footer>.
- Avoid using headings purely for styling. Use CSS classes instead.
Example:
<main>
<h1>The SEO Guide for Developers</h1>
<section>
<h2>Technical SEO Foundations</h2>
<p>…</p>
</section>
</main>
Good structure helps both screen readers and search algorithms.
3.4 Image Optimisation & Alt Text
Images can heavily impact performance and accessibility.
Developers can:
- Use modern formats like WebP or AVIF where supported.
- Implement responsive images with srcset and sizes.
- Set explicit width and height to reduce layout shifts.
- Use native lazy loading with loading="lazy" where appropriate.
Example:
<img
src=”/images/seo-guide-hero.webp”
srcset=”/images/seo-guide-hero-800.webp 800w, /images/seo-guide-hero-1600.webp 1600w”
sizes=”(max-width: 800px) 100vw, 800px”
alt=”Developer working on website code to improve SEO”
loading=”lazy”
/>
Alt text usually comes from content or UX teams, but you’re responsible for making sure it’s implemented, not stripped, and not duplicated across unrelated images.
3.5 Language & Internationalisation
The lang attribute tells browsers and search engines what language your content is in.
- Set the language on the <html> element, e.g. <html lang="en">.
- For multilingual sites, implement correct hreflang tags and clear URL patterns (/en/, /fr/, etc.).
- Ensure that right-to-left languages set dir="rtl" where required.
Example:
<html lang=”en-AU”>
This helps search engines show the right pages to the right audience.
3.6 Internal Linking
Internal links are one of the simplest and most powerful SEO tools.
As a developer, you can:
- Ensure navigation is built in HTML links (not just JS events or forms).
- Use consistent link paths and avoid creating multiple URLs for the same destination.
- Implement context links in templates where relevant (e.g. “related posts” or “popular guides”).
- Support breadcrumbs and category-based navigation.
Internal links help:
- Distribute authority between pages
- Guide crawlers through your site
- Highlight which pages are most important
4. Performance, Core Web Vitals & UX
Search engines care deeply about user experience. Core Web Vitals are the metrics Google uses to evaluate that experience.
4.1 Key Performance Metrics
Some important metrics you influence:
- Largest Contentful Paint (LCP): How quickly the main content appears
- Interaction to Next Paint (INP): How quickly the page responds to user interactions (replaces FID)
- Cumulative Layout Shift (CLS): How stable the layout is while loading
- Time to First Byte (TTFB): Server response time
Fast, stable pages usually perform better in search and lead to higher conversions.
4.2 Practical Ways Developers Improve Speed
You don’t need to guess. Use tools like Lighthouse, PageSpeed Insights or WebPageTest, then apply fixes such as:
- Optimise images: Compress, use responsive sizes, and modern formats
- Minify and bundle assets: Minify CSS/JS and avoid unnecessary bloat
- Code splitting: Load only what’s needed for the initial view
- HTTP caching: Use proper cache headers, ETags, and versioned file names
- CDN: Serve static assets via a CDN close to your users
- Preload critical resources: Fonts, above-the-fold images, and key CSS
- Reduce JS execution time: Remove unused libraries, avoid heavy on-load work
Example of preloading a critical font:
<link rel=”preload” href=”/fonts/inter-roman.woff2″ as=”font” type=”font/woff2″ crossorigin=”anonymous” />
4.3 Responsive & Mobile-Friendly Design
Google predominantly uses mobile-first indexing, so the mobile version of your site is what counts most.
Make sure:
- meta viewport is properly set:
<meta name=”viewport” content=”width=device-width, initial-scale=1″ />
- Layouts adapt to different screen sizes via CSS (Flexbox, Grid).
- Tap targets are large enough and spaced out.
- Navigation is easy to use on touch devices.
If your mobile experience is poor, rankings and conversions will suffer.
4.4 Preventing Layout Shifts (CLS)
- Always specifying width and height on images and iframes.
- Reserving space for ads or embedded content.
- Avoiding inserting new content above existing content unless in response to user interaction.
- Using system fonts or font-display strategies to reduce layout changes when web fonts load.
Example:
<img src=”/images/logo.webp” alt=”Company logo” width=”200″ height=”60″ />
5. JavaScript SEO: Making JS Frameworks Search-Friendly
5.1 CSR vs SSR vs Hydration
- Client-Side Rendering (CSR): Content is rendered via JS in the browser. If bots struggle to execute JS or are delayed, they may see little or no content.
- Server-Side Rendering (SSR): HTML is rendered on the server and sent to the client. JS then hydrates the page. This is usually more SEO-friendly.
- Static Site Generation (SSG): Pages are prebuilt as static HTML and served quickly, often via a CDN.
For critical content that needs to rank, SSR or SSG is usually safer.
5.2 Practical JS SEO Tips
- Ensure important content exists in the initial HTML whenever possible.
- Avoid using hash # routes as canonical URLs (e.g. /page#section for primary content).
- Make navigation links regular <a> elements with real href attributes.
- Avoid blocking vital JS or CSS resources in robots.txt.
- Test with tools like “View Source”, “Inspect” and “URL Inspection” in Google Search Console to see what Google actually sees.
If you must use heavy client-side rendering, consider hybrid approaches or dynamic rendering for bots where appropriate.
6. Structured Data & Rich Results
Structured data helps search engines understand what your content represents (article, product, FAQ, event, etc.) and can unlock rich results in the SERPs.
6.1 JSON-LD for Articles
For blog posts or guides, use Article or BlogPosting schema:
<script type=”application/ld+json”>
{
“@context”: “https://schema.org”,
“@type”: “Article”,
“headline”: “The SEO Guide for Developers”,
“author”: {
“@type”: “Organization”,
“name”: “Example Agency”
},
“datePublished”: “2025-11-01”,
“dateModified”: “2025-11-01”,
“mainEntityOfPage”: {
“@type”: “WebPage”,
“@id”: “https://www.example.com/web-development/seo-guide-for-developers”
}
}
</script>
6.2 Breadcrumb & FAQ Schema
Breadcrumbs:
<script type=”application/ld+json”>
{
“@context”: “https://schema.org”,
“@type”: “BreadcrumbList”,
“itemListElement”: [{
“@type”: “ListItem”,
“position”: 1,
“name”: “Web Development”,
“item”: “https://www.example.com/web-development/”
},{
“@type”: “ListItem”,
“position”: 2,
“name”: “The SEO Guide for Developers”,
“item”: “https://www.example.com/web-development/seo-guide-for-developers”
}]
}
</script>
FAQ schema can be added if you include an FAQ section (see below). This can increase SERP real estate and click-through rates.
7. Collaboration & Workflow: Making SEO Part of Dev Process
SEO is much more effective when it’s part of your normal development lifecycle.
7.1 Checklists for New Builds
Create or adopt a developer SEO checklist that covers:
- Crawlability (robots.txt, meta robots, canonical tags)
- URL patterns and redirection rules
- Performance budgets and Core Web Vitals targets
- Structured data implementation
- Mobile and accessibility testing
- XML sitemaps and error handling
7.2 Integrating SEO into CI/CD
Where possible:
- Run automated Lighthouse or similar performance tests on key templates.
- Lint for common SEO issues (missing titles, multiple H1s, invalid structured data).
- Check for broken internal links and unexpected 404s after deployments.
This turns SEO from a one-off “audit” into an ongoing quality practice.
8. Jargon Buster (Developer-Friendly SEO Terms)
- On-page SEO – Optimisations made directly on a page (content, titles, headings, internal links, images, etc.).
- Technical SEO – Backend and structural work that helps search engines crawl, render and index your site correctly (URLs, sitemaps, speed, JS, server config).
- Keywords – Words or phrases users type into search engines. Pages are optimised around relevant keywords that match search intent.
- Core Web Vitals – A set of user-centric performance metrics (LCP, INP, CLS) that influence search visibility and user satisfaction.
- Structured data – Machine-readable markup that explains what your content is about (articles, products, FAQs, events, etc.), often using JSON-LD.
