Hey everyone! I run a digital agency called Aqva Marketing, where we handle both web development and SEO. I often see a massive disconnect between how developers build a site and how search engines read it.
Most common things I see missing in custom-built sites:
Ignoring Semantic HTML (using <div> for everything).
Terrible Core Web Vitals (especially LCP due to unoptimized hero images).
Client-Side Rendering (CSR) without proper pre-rendering for crawlers.
As developers, how much attention do you actually pay to technical SEO while building a project? Do you rely on marketing teams to fix it later, or do you bake it into your architecture? Let's discuss!
The biggest one I keep seeing: treating meta titles and descriptions as an afterthought. Developers will spend weeks perfecting an app, then write a 10-word meta description that's just the site name repeated.
The second thing — and this one really hurts small business sites — is no structured data. A local business with zero schema markup is invisible to rich results. It takes maybe 30 minutes to add basic Organization or LocalBusiness schema and the difference in click-through rate is measurable.
For the Core Web Vitals point: LCP is usually the killer. Most devs don't realize their hero image is loading uncached from a CDN with no fetchpriority="high" hint. One attribute change, massive improvement.
One of the biggest technical SEO mistakes I still see developers making is treating SEO like a “post-launch task” instead of part of the architecture from day one.
You already mentioned semantic HTML and Core Web Vitals — both are huge — but I’d add poor crawlability as another major issue. A lot of modern sites rely heavily on JavaScript frameworks without thinking about how search engines actually render pages. If the content, metadata, or internal links depend entirely on client-side rendering, indexing problems usually follow.
Another common one is ignoring proper internal linking and heading structure during development. I’ve seen beautifully designed websites where every section is just nested divs with no meaningful hierarchy at all. Looks great visually, but search engines lose context fast.
Personally, I think developers who understand even basic technical SEO have a huge advantage today. It’s much easier to build performance, accessibility, and crawlability into the project early than trying to “SEO-fix” everything later.
At Apklounge, I’ve been experimenting with balancing fast-loading pages and SEO-friendly structure for gaming-related content, and even small optimizations to image delivery and page structure can noticeably improve visibility.