Configure ProGuard Rules to Enable Obfuscation {#tap-to-phone-configure-proguard-rules}
=======================================================================================

Follow these steps to configure ProGuard rules that enable obfuscation.

1. To enable obfuscation for any of your build types, define the setting in the relevant *build.gradle* file for your app.

   ```
   buildTypes {
       release {
           isMinifyEnabled = true
           proguardFiles(getDefaultProguardFile("proguard-android-optimize.txt"), "proguard-rules.pro")
       }
   }
   ```
2. If you are using ProGuard as an obfuscation tool in your app, add these rules to the *proguard-rules.pro* file.

   ```
   # OkHttp
   -keepattributes Signature
   -keepattributes *Annotation*
   -dontwarn com.squareup.okhttp.**
   -keep class com.squareup.okhttp.* { *; }
   -dontwarn okio.**

   # Acceptance Devices
   -keep class io.mpos.** { *; }
   -dontwarn io.mpos.**
   -keep class com.visa.vac.tc.** {*;}
   -keep class com.nimbusds.jose.** {*;}
   -keep class org.bouncycastle.** {*;}
   -keep class retrofit2.** { *; }
   -keep interface retrofit2.** { *; }
   -keep class com.visa.auth.** { *; }
   -dontwarn com.visa.auth.**
   -keep class androidx.** { *; }

   # Visa Sensory Branding
   -keep class com.visa.SensoryBrandingView

   # Mastercard Sonic Branding 
   -keep class com.mastercard.sonic.BuildConfig {*;}
   ```