A script that utilizes Xcode's command line tools to enable Just-In-Time (JIT) compilation for apps running on iOS, iPadOS, and other related OS families.
- Mac with Xcode 16 and its Xcode Command Line Tools installed.
- Target device has Developer Mode enabled.
- Target device is paired with Xcode on Mac.
- No warnings are shown at: Xcode > Window > Device and Simulators > Devices > [your target device].
Ensure your paired device is connected to your Mac over USB, or on Wi-Fi on the same local network.
Then, in the project directory, run:
./xcjit '<device name>' '<app/process name>'e.g.,
./xcjit 'iPad Pro' 'UTM'You can softlink or copy the script to a directory in your PATH for quick access.
JIT on iOS and related OS families are "enabled" by simply attaching a debugger to the target app, and then immediately detaching it. Apps being debugged go into a lower security state that allows apps like UTM to use JIT, which isn't usually possible.
If you already have Xcode installed, this script provides a lightweight alternative that uses Xcode's built-in tools to enable JIT, without any additional software or dependencies.