This article is based on reporting originally published by ZDNet in August 2020, covering data shared by Google’s Open Source Programs Office.
Google Publishes Five-Year Open-Source Snapshot
Google released a “by the numbers” overview of its open-source activity spanning 2015 through 2019, giving developers and organizations a concrete look at how one of the world’s largest technology companies engages with the broader open-source ecosystem. The data covers contributions to both Microsoft-owned GitHub and Google’s own internal Git hosting service, git-on-borg, which is the primary host for large Google-led projects such as Android and Chromium.
Employee Participation: 12,500 Contributors in 2019
According to Google, more than 9% of Alphabet’s full-time employees actively contributed to public repositories across git-on-borg and GitHub in 2019. In absolute terms, that translates to just under 12,500 employees—up from approximately 10,000 in 2018 and around 5,000 in 2015, representing a roughly 2.5× increase over the five-year period.
The steady growth in contributor headcount suggests that open-source participation has become increasingly embedded in Google’s engineering culture, rather than remaining the domain of a specialist group.
Repository Footprint: 8,000+ Public Repos on GitHub
Google hosts more than 8,000 public repositories on GitHub and over 1,000 public repositories on git-on-borg. Combined, the company says it has doubled its total number of public repositories over the five years to 2019.
Beyond its own hosted repositories, Google employees were active in over 70,000 repositories on GitHub in 2019 and pushed commits or opened pull requests in more than 40,000 repositories—a figure that underscores the breadth of engagement outside Google’s own projects.
Contribution Volume: Issues, Pull Requests, and Push Events
Sophia Vargas, a researcher at the Google Open Source Programs Office, explained the metrics Google chose to highlight—and why they differ from raw commit counts:
“For contribution volume on GitHub, we chose to focus on push events, opened, and merged pull requests instead of commits, as this metric on its own is difficult to contextualize. Note that push events and pull requests typically include one or more commits per event.”
— Sophia Vargas, Google Open Source Programs Office
Using those metrics, Google’s 2019 GitHub activity included:
- 570,000+ issues created
- 150,000+ pull requests opened
- 36,000+ push events
Compared with 2015, the number of issues created and push events had doubled, while open pull requests had tripled. More than 80% of pull requests opened by Google employees were closed and merged into active repositories—a metric Vargas cited as evidence of contribution quality, not just volume.
Diversification Across Repositories
One of the more meaningful trend lines in the data is how Google’s contributions have spread across a wider set of projects over time. In 2015, the top 25 repositories absorbed approximately 40% of Google’s opened pull requests. By 2019, that figure had dropped to around 20%—meaning contributions were distributed far more broadly across the ecosystem.
“For us, this indicates a healthy expansion and diversification of interests, especially given that this activity represents both Google, as well as a community of contributors that happen to work at Google.”
— Sophia Vargas, Google Open Source Programs Office
How Google’s Metrics Compare to Microsoft’s
When Microsoft announced its acquisition of GitHub in 2018, it positioned itself as the most active organization on the platform, citing two million commits to projects. Google deliberately chose a different set of indicators—push events and pull request activity—arguing that raw commit counts are hard to interpret without context (a single pull request may contain dozens of commits, or a single commit may represent months of work).
The methodological difference matters for DevOps teams benchmarking their own contribution policies: commit volume can be gamed or inflated by automated tooling, while merged pull request rates and cross-repository breadth are harder to manufacture and arguably more meaningful signals of genuine community engagement.
Notable Google Open-Source Projects
GitHub’s 2019 State of the Octoverse report (published November 2019) ranked projects by contributor count. Microsoft’s Visual Studio Code topped the list with approximately 19,100 contributors, followed by Azure Docs (14,000 contributors). Google’s Flutter UI framework came in third with around 13,000 contributors.
Other high-traffic Google-originated projects included:
- TensorFlow – the machine learning framework widely used in AI/ML pipelines
- Kubernetes – the container orchestration system now governed by the Cloud Native Computing Foundation (CNCF)
- OSS-Fuzz – a continuous fuzzing service that integrates with open-source projects to automatically find security vulnerabilities and bugs
Vargas specifically highlighted OSS-Fuzz as an example of Google’s contributions to open-source security infrastructure—it is publicly available on GitHub and can be integrated by any project maintainer looking to harden their codebase against memory safety bugs and other low-level vulnerabilities.
Key Takeaways for DevOps and Engineering Leaders
- Commit count alone is a weak proxy for open-source contribution quality. Merged pull request rates and cross-repository breadth provide better signal.
- Employee participation scales with deliberate culture investment. Google’s contributor headcount growing from 5,000 to 12,500 in five years does not happen by accident—it requires tooling, policies, and management buy-in.
- Diversification of contributions reduces dependency on a small set of flagship projects and builds goodwill across the broader ecosystem.
- Security tooling is a form of open-source contribution. Projects like OSS-Fuzz provide compounding value well beyond Google’s own codebases.
Original reporting by ZDNet, August 2020. Data and quotes sourced from Google’s Open Source Programs Office.