As the title says, SEO and Web Dev are more interconnected than any point in the past, and it's looking more and more likely that that relation will only get closer with time.
Many "under the hood" factors are playing a stronger role in Google's ranking algorithm for websites. The old methods of ranking, relying on external backlinks, have been abused to the point where policing bad behavior and blackhat methods has become a monumental task.
More and more, Google is weighing two other key areas much more heavily in their criteria for the positioning in the SERPS:
1) Quality and relevance of content - which through the use of AI Technology, they have gotten quite good at without human intervention
2) Technical "on site" optimizations, which is what I will be discussing today.
It has been common knowledge, something Google has been very transpaqrent about (one of the few things) that SSL (https) has been a ranking factor since 2013.
This ranking factor has only strengthened, and has been joined by a number of other factors.
At SocialSEO, we have been working hard to keep on top of thsee factors and learning the under the hood mechanics that make these work.
These factors include:
Page speed (sites that take longer than 3 seconds to load will suffer greatly in the SERPS)
Proper usage of Schema Markup
Properly Coded Website
Absence of Adobe Flash (slows down sites and will get your site downgraded bigtime)
Image Alt Tags
Proper placement of Header tags (H1, H2 etc)
Internal linking structure
HTML errors/W3C validation
Just to name a few. That being said, it will be interesting to see, in the coming years, just how much the landscape will be changing.
Personally, I predeict a whole lot more crossover between SEO and WebDev, and vice versa. All signs certainly seem to point that way.