Systems | Development | Analytics | API | Testing

Why DORA metrics, the delivery numbers we've trusted for a decade, tell us less than they used to, and what engineering leaders should watch instead. At Bitrise, we run mobile CI/CD workflows for thousands of teams, so we see the raw material behind thousands of DORA dashboards, down to every commit, every pull request, every build, and every green check and red X.

Mitchell Hashimoto wrote that in April 2026, on a day that he couldn’t do any PR review for almost 2 hours because GitHub Actions was down. Again. In the same blog post, he announced that Ghostty, the terminal emulator project he maintains, was leaving GitHub. This wasn’t a split-second decision, based on one outage. In the month leading up to the post, the HashiCorp co-founder had been keeping a journal, marking an X next to every date when a GitHub outage interfered with his work.

On October 17, 2026, the developer world learned that the private keys of eight intermediate certificate authority (CA) certificates from eMudhra had been compromised. In this article, I’ll explain how that affects the Bitrise environment powering your Bitrise CI jobs, Build Hub runners, and Remote Developer Environments.

Over-the-air (OTA) updates let you fix a bug in your React Native app and get it to users the very same day, without waiting for App Store or Google Play review. That speed is why teams adopt OTA. It’s also where things can go wrong: push a JavaScript bundle to the wrong app version and a small bug becomes a crash.

When the engineering team first described what they wanted to build, I nodded along like I knew exactly what they meant. Gradle task inputs. Cache misses. Invocation diffs. Sure, totally. I wrote it all down and quietly Googled half of it afterward. That was my introduction to designing Gradle Task IO for Bitrise Build Cache, a feature built to help engineering teams understand why builds are slow and get more value from build caching.

For many teams, Bitrise Insights means build duration and failure rate. Those are good starting points to evaluate your CI performance, but they often fall short when it comes to understanding questions about speed and quality.

With Remote Build Execution (RBE) your Bazel build and test compilations run in parallel across many remote workers at once, instead of in series, one by one on a single machine.

Build tools have relied on it for years to avoid redoing work that hasn't changed. In React Native CI it's still a bit of a secret sauce: a fingerprint-based caching technique that can make your builds several times faster, yet one that surprisingly few teams have switched on. The premise is simple: most of the time you're only changing JavaScript, so most of the native modules are reusable.

In March 2024, Microsoft announced it would retire App Center in March 2025. For a lot of mobile teams, the first question was simple: what now? I was on the Release Management team at the time, and we thought CodePush was worth pursuing. We wrote up the case, got it onto the roadmap, and then waited. Nobody could say yet whether it would become a valuable product, and a team our size has to pick its bets carefully.

You’ve probably encountered the online conversations about GitHub’s AI scaling challenges. A lot of the chatter is about how forgiving (or not) users should be to GitHub in light of inexorable traffic increases but also GitHub’s own decision-making. There is certainly irony in the fact that it was a swashbuckling GitHub, against the objections of many open source developers, that pressed Copilot on the industry.