# Travis CI: xcodebuild exited with 65 on iOS simulator tests (flaky, simulator not warmed up)
## The problem
iOS simulator tests on Travis CI (macOS/Xcode images) failed flakily with "xcodebuild exited with 65" - the same tests passed locally and on reruns with no code changes. Multiple reporters saw it across many repos: in a build matrix, a random target would fail each run. The suspected cause was the simulator not being warmed up when xcodebuild started the tests.
## The verified fix
The flaky exit code 65 comes from the iOS simulator not being ready when tests start. Pre-start/warm the simulator at the beginning of the build before running xcodebuild (e.g. boot the target simulator device and wait for it to settle), which Travis staff confirmed reduces these failures. Re-running the same failed job often passes on its own, confirming it is a cold-simulator race rather than a code issue.
Source: https://github.com/travis-ci/travis-ci/issues/6675