fix: production build config

app/build.gradle.kts

@@ -1,4 +1,9 @@
 import com.google.protobuf.gradle.*
+import java.util.Properties
+
+val localProps = Properties().apply {
+    load(rootProject.file("local.properties").inputStream())
+}
 
 configurations.all {
     resolutionStrategy {
@@ -36,13 +41,24 @@ android {
 
     testBuildType = "benchmark"
 
+    signingConfigs {
+        create("release") {
+            storeFile = file(localProps["KEYSTORE_PATH"] as String)
+            storePassword = localProps["KEYSTORE_PASSWORD"] as String
+            keyAlias = localProps["KEY_ALIAS"] as String
+            keyPassword = localProps["KEY_PASSWORD"] as String
+        }
+    }
+
     buildTypes {
         release {
-            isMinifyEnabled = false
+            // isMinifyEnabled = true          // Enables R8/ProGuard shrinking
+            // isShrinkResources = true        // Removes unused resources
             proguardFiles(
                 getDefaultProguardFile("proguard-android-optimize.txt"),
                 "proguard-rules.pro"
             )
+            signingConfig = signingConfigs.getByName("release")
         }
         create("benchmark") {
             initWith(buildTypes.getByName("release"))

app/proguard-rules.pro

@@ -19,3 +19,6 @@
 # If you keep the line number information, uncomment this to
 # hide the original source file name.
 #-renamesourcefileattribute SourceFile
+
+# Keep all protobuf generated message classes and their fields
+-keep class * extends com.google.protobuf.GeneratedMessageLite { *; }