If you try to build your Android app with Shake SDK and a ProGuard version older than 6.0, you'll get an error similar to this one:
Unknown option '-if' in line 43 of file '\proguard.txt'
To resolve it, update your app's ProGuard version to 6.0 or newer.
If you have any other questions, don't hesitate to contact us through the Intercom bubble.
Or even better, join our Slack Community and get in touch with our developers within a few minutes.