Over the past year, while Git traffic grew exponentially, 99.99999% of the Git repositories on GitHub began living in two places at once: our own data centers and Azure. The rest are among the busiest on the platform, and they’re held back by just one thing: a 25ms round trip. In an earlier blog pos...

Working with outside collaborators can add more work for a repository owner. You need to confirm who still needs access, change permissions as projects evolve, and archive repositories once they’ve served their purpose. To keep up, repository owners need to track collaborators, deadlines, and follow...

Maintainers look at star history to answer a practical question: did a launch, release, or event change a project’s trajectory? To reconstruct that curve from the GitHub API, tools had to request pages of stargazer records (each person who currently stars the repository and when they starred it), ke...

Every day on GitHub, millions of developers build the products their customers rely on, contribute to open source, and pursue personal projects. GitHub’s architecture has changed steadily over the years to support that work and the growing demands of the developers and organizations who depend on it...

The Primer Design System powers many of the experiences you see on GitHub today. From buttons to banners to breadcrumbs, these foundational components are required to be accessible, flexible, and performant across a wide variety of scenarios. Back in 2023, the number of components on certain pages b...

Broad refactors and migrations often have to land as one change. Stacked pull requests are a great way to split work into smaller changes, which makes reviews easier and helps teams ship with less risk. But some changes, like this one, can’t be split cleanly. That leaves you with a single pull reque...

Output quality is important when working with AI coding agents, but true efficiency comes from getting work done quickly, efficiently, and with the right context. That’s why token count of individual interactions alone isn’t a meaningful measure of efficiency. The goal shouldn’t be to use fewer toke...

More than one in four images on the web’s most popular home pages have alt text that’s missing, vague, or copied from adjacent images. That’s from WebAIM’s 2026 WebAIM Million report, which found that alt text,an HTML attribute containing text describing the content of an image, was missing on 16.2%...

Java developers no longer have to rely on Java framework-specific approaches to drive AI from their enterprise apps. While it is true that Langchain4j empowered developers by disintermediating specific AI vendors, you still had a dependency on Langchain4j. And with Spring AI, well, of course you had...

Think about the last big feature you shipped. Be honest. Did you cram it into one giant pull request, or did you split it into smaller scoped pull requests? For years, you have silently had to decide between watching a pull request grow so large that reviewing it becomes a nightmare or breaking it i...

Suppose a user searches for café and your corpus contains CAFÉ, or they type straße and you’ve stored STRASSE. To make these count as matches, you need a canonical form that erases case distinctions, so that two strings which differ only in case compare equal. That form is case folding, and it shows...

If you maintain an active repository, you know the feeling. You open your notifications on a Monday morning and there they are: five, 10, sometimes a dozen Dependabot pull requests, each bumping a single dependency by a single patch version. Individually, every one of them is helpful. Collectively, ...

The most expensive part of a small feature request used to be writing the code. Now it’s usually the meeting about whether or not to write the code. That’s a real shift, and it quietly breaks a lot of engineering instincts. Engineers learn early that most “small asks” aren’t small: they need tests, ...

Give an agent better tools and it should do better work. That’s the instinct, anyway. When you open a pull request, Copilot code review reads the diff and explores the surrounding code to find the problems that matter before they ship. To do that, it used its own code exploration tools. So when we s...

“Where are the docs?” It’s a question nobody on a product team enjoys answering. The honest reply is usually some variant of “behind.” A writer is staring at a closed pull request, trying to reverse-engineer what changed. The pull request’s author has already moved on. By the time the doc actually p...

When you’re working through a backlog—opening an issue, jumping to a linked thread, then back to the list—latency isn’t just a metric. It’s a context switch. Even small delays add up, and they hit hardest at the exact moments developers are trying to stay in flow. It’s not that GitHub Issues was “sl...

Did you know that, at GitHub, we host all of our own source code on github.com? We do this because we’re our own biggest customer—testing out changes internally before they go to users. However, there’s one downside: If github.com were ever to go down, we wouldn’t be able to access our own source co...

Pull requests are the beating heart of GitHub. As engineers, this is where we spend a good portion of our time. And at GitHub’s scale—where pull requests can range from tiny one-line fixes to changes spanning thousands of files and millions of lines—the pull request review experience has to stay fas...

I may have just automated myself into a completely different job… This is a familiar pattern among software engineers, who often, through inspiration, frustration, or sometimes even laziness, build systems to remove toil and focus on more creative work. We then end up owning and maintaining those sy...

For years, accessibility feedback at GitHub didn’t have a clear place to go. Unlike typical product feedback, accessibility issues don’t belong to any single team—they cut across the entire ecosystem. For example, a screen reader user might report a broken workflow that touches navigation, authentic...

So much of what you interact with on GitHub depends on search—obviously the search bars and filtering experiences like the GitHub Issues page, but it is also the core of the releases page, projects page, the counts for issues and pull requests, and more. Given that search is such a core part of the ...

Most people think ASCII art is simple, and a nostalgic remnant of the early internet. But when the GitHub Copilot CLI team asked for a small entrance banner for the new command-line experience, they discovered the opposite: An ASCII animation in a real-world terminal is one of the most constrained U...

To keep a platform like GitHub available and responsive, it’s critical to build defense mechanisms. A whole lot of them. Rate limits, traffic controls, and protective measures spread across multiple layers of infrastructure. These all play a role in keeping the service healthy during abuse or attack...

Today, we’re announcing some changes that will improve the security of accessing Git data over SSH. What’s changing? We’re adding a new post-quantum secure SSH key exchange algorithm, known alternately as sntrup761x25519-sha512 and [email protected], to our SSH endpoints for accessi...

In my spare time I enjoy building Gundam models, which are model kits to build iconic mechas from the Gundam universe. You might be wondering what this has to do with software engineering. Product engineers can be seen as the engineers who take these kits and build the Gundam itself. They are able t...

Originally, Issues search was limited by a simple, flat structure of queries. But with advanced search syntax, you can now construct searches using logical AND/OR operators and nested parentheses, pinpointing the exact set of issues you care about. Building this feature presented significant challen...

In part one of our design system annotation series, we discussed the ways in which accessibility can get left out of design system components from one instance to another. Our solution? Using a set of “Preset annotations” for each component with Primer. This allows designers to include specific pre-...

When it comes to design systems, every organization tends to be at a different place in their accessibility journey. Some have put a great deal of work into making their design system accessible while others have a long way to go before getting there. To help on this journey, many organizations rely...

At GitHub, we’re committed to making our tools truly accessible for every developer, regardless of ability or toolset. The command line interface (CLI) is a vital part of the developer experience, and the GitHub CLI is our product that brings the power of GitHub to your terminal. When it comes to ac...