How GitHub Gets 1.3 Billion Visitors From Open Source SEO

GitHub is a cloud based code repository SaaS with a suite of software development collaboration tools. According to SimilarWeb, GitHub receives 355M visits a month.

As a non-coder only casually aware of GitHub, I assumed the bulk of that traffic was from direct visits from coders and teams using GitHub to collaborate. But it turns out that 1/3 of that traffic comes from organic search. With another 16% coming from referral links from other sites.

That’s roughly 107 millions visits a month from organic search, or 1.3 billion visits a year.

Oh and all that referral traffic?

That comes from the 3.32 billion backlinks to the site, giving GitHub an Ahrefs SEO domain rating of 96 out of 100. Not to mention 682 million inbound visitors a year.

Source: SimilarWeb

These impressive SEO stats sparked my curiosity, so I decided to dig deeper into GitHub’s SEO strategy and what makes it so successful.

Let’s break it down together and explore…

  • What an open source SEO growth engine looks like, and the subtle factors that unlocked billions in organic search traffic for GitHub.

  • Why forking is one of GitHub’s biggest SEO amplifiers.

  • What a conversation loop is, why it’s critical for GitHub’s SEO success, and how to build one into your SaaS.

GitHub’s Billion Visitor Open Source Growth Engine

The real secret sauce behind GitHub’s SEO success is their open source code repositories. These are publicly accessible pages that give coders anywhere in the world access to the code from open source projects.

GitHub also offers users the ability to create private code repositories, and this is where teams collaborate on “for profit” software projects (often using GitHub’s paid team collaboration features, the source of GitHub’s SaaS revenue).

But the private repositories are just that: private. Only users with permission have access to them. Which means they remain invisible to Google’s eyes.

But if you set a code repository’s permissions to be publicly accessible, Google’s crawler can index it. And according to an analysis by Simiotics, there are 128,411,417 publicly accessible repositories on GitHub as of February 2020.

A quick check of Google’s search results shows a slightly smaller number of pages. “Only” 69,400,000 pages indexed.

SaaS SEO Takeaway #1: Going “Public” With User Permissions to Open the Flood Gates of User Generated Content

GitHub almost has SEO baked into the DNA of its product.

But you can easily imagine a world where GitHub as a SaaS product only focused on hosting private code repositories. After all, this is where their real revenue ultimately comes from – software companies who want to collaborate in private.

Not every SaaS has an obvious open source ecosystem to exploit like GitHub did. But it’s worth zooming out the lens on your SaaS and looking for ways that your customers (or overlooked segments of users) might use your product to collaborate in a public way.

For example, note taking apps like Notion and Mem could have only provided private sharing of notes created in their software. But they chose to add functionality that made it possible to publish notes publicly.

Questions to consider for your SaaS:

What user functionality could be unlocked by adding public/private user permission options to your product?

In what ways could public collaboration add value to your existing user workflows?

In what ways are your users already collaborating behind the scenes, outside of your product?

A Forked Path to Growing User Generated Content

The next interesting thing about GitHub’s SEO is the forking feature. Forking is where a user essentially creates a copy of a code repository for their own use.

In the case of a publicly accessible code repository, any user can make a copy of it. Once it’s copied the user is free to make whatever changes they like to it. And can choose to either keep their copy of it private or also make it publicly accessible.

The user can also request that changes made to their personal copy be added to the code of the original repository, but whether these changes are accepted is up to the original owner.

This forking feature sits at the core of GitHub’s collaboration functionality. But it’s also an incredible SEO amplifier, acting as a growth accelerant for the collection of user generated content GitHub hosts.

SaaS SEO Takeaway #2: Make It Easy for Users to Collaborate Around Publicly Accessible Outputs

GitHub’s DNA goes beyond just producing publicly accessible, user generated content pages (which are a fairly common feature of a variety of platforms).

It also bakes in a collaboration element that makes it incredibly easy for users to duplicate existing user generated content, and then put their own spin on it. This acts essentially like a virus, with each new iteration of the content evolving to a different version of itself. And then spreading to the next set of users (or not, depending on the evolutionary viability of that iteration).

Again, not every SaaS has an obvious open source ecosystem where this kind of collaboration mechanism makes sense. But why not let users decide? In addition to a publicly accessible privacy option, you could also add an “open source” option indicating that content was free for anyone to re-use or iterate how they wish.

This could be a good fit for note taking applications, publishing tools, design tools, or anything involving the creation of intellectual property. It might also fit with intelligence tools involving data or analysis.

Questions to consider for your SaaS:

How can you make it easier for users to iterate on public facing outputs from other users?

What safeguards or assurances might help users feel more confident about collaborating publicly?

What would a culture of open, public collaboration look like in your market?

Can You Turn Your SaaS Into a Hub?

The final component in GitHub’s SEO growth engine is actually right in their name – it’s the “Hub” in GitHub.

Like I mentioned earlier, 16% of GitHub’s traffic comes from their 3.32 billion backlinks. These links drive 57 million visitors a month to GitHub (in addition to fueling their enormous SEO authority).

Why are so many sites linking to GitHub? Because they are, indeed, the hub of collaboration for millions of coding projects. But most importantly, they have positioned themselves at the center of conversations happening all around the web for each project.

This means whenever a coding project is referenced or discussed anywhere – whether it’s on a discussion board, in a blog, a wiki, a resource directory, or on the website of the individual project – there will be a link back to the project’s GitHub page.

The public nature of the collaboration that GitHub enables may be the biggest factor behind their SEO success.

SaaS SEO Takeaway #3: Look for The Public Conversations That Your SaaS Can Add Value To, Then Build a Conversation Loop

A key factor to GitHub’s enormous SEO success is that they have put themselves in the middle of discussions being held across a wide variety of platforms and sources outside GitHub.

Rather than just allowing collaboration between two individuals on GitHub’s own platform, GitHub’s open source projects are widely shared and discussed on a variety of public channels.

GitHub also doesn’t just facilitate a one time conversation, but puts itself at the center of an ongoing discussion. As a coding project evolves new conversations happen, building even more links into the project.

This creates a conversation loop that not only drives ever growing traffic and links to GitHub over time, but also improves the actual output of the product – ever evolving and improving open source code.

As the output of the collaboration improves through this conversation loop, the output’s value also grows. This in turn attracts more and more links from those who see value in the output.

Questions to consider for your SaaS:

What public conversations are happening in your market that could be tied into the user workflows your SaaS facilitates?

How can your SaaS add value to conversations happening in your market?

What conversation loops can be created with outputs from your SaaS? How can these conversation loops refine and improve your product’s outputs?

A Note on Future Collaboration Systems

GitLab celebrates IPO on October 14, 2021 (Source: Nasdaq)

GitHub’s SEO is just as much a case study of Git, the underlying open source version control system used by GitHub and others (like GitLab that recently reached a $15B market cap in its IPO). Most of the SEO levers we discussed above are rooted in the dynamics of Git itself, and are manifested through GitHub’s web based interface.

When looking for ways to emulate GitHub’s SEO success in your own SaaS, perhaps one of the best places to start could be in existing and emerging open source collaboration systems. With the rise of Web 3.0 and its push toward decentralization, the next big collaboration system could be quietly waiting for you to unlock its full potential with your SaaS.

Or maybe your SaaS is the next big collaboration system, at least in your own small corner of the web. You don’t need to build the next GitHub. There are conversations to connect and collaboration waiting to be unlocked in niches big and small.