After adding German and Spanish to our Flutter app, release builds showed raw keys like checkout.pay_button instead of text. The new translation files were declared as assets only on one laptop, never in the repository. How we found it, fixed the declarations and moved to compile-time localizations.
Our Flutter app grew from five screens to sixty, and every change touched widgets, API calls and state in the same file. The structure we moved to: feature-first folders, with UI, state, repository and service layers whose dependencies point one way, and how each layer is tested.
Releasing our React Native app used to take a developer most of a day: bump versions, sign, build two platforms, upload, fill in notes. We moved it to fastlane lanes run from CI on a git tag. Project layout, versioning, signing with match, TestFlight and Play internal tracks, secrets, and what still needs a human.
Our delivery app tracks a driver's route during a delivery. After targeting Android 14, tracking stopped minutes after the screen turned off, and on some devices the app crashed when tracking started. Android 14 requires a declared foreground service type and permission. How we fixed it.
After moving iOS builds to a self-hosted Mac runner with fastlane match, archives hung for an hour at the codesign step, or failed with errSecInternalComponent. codesign was waiting for a keychain it could not unlock without a GUI prompt. How setup_ci, a temporary keychain and the key partition list fixed it.
Our React Native app ran perfectly in debug, then the release APK closed instantly on every device. adb logcat showed a ClassNotFoundException for a class used through reflection by a native SDK, which R8 had removed during minification. How we read the crash, wrote keep rules and verified with mapping.txt.
Our yearly Apple distribution certificate expired, we created a new one, and every archive failed: the provisioning profile doesn't include the signing certificate. Profiles embed the certificates they trust. How we regenerated profiles, cleaned keychains and verified signing identities.