perf: increase release optimizations

app/build.gradle.kts

@@ -31,6 +31,28 @@ android {
         }
     }
 
+    androidComponents {
+        onVariants(selector().withBuildType("release")) {
+            it.packaging.resources.excludes.apply {
+                // Debug metadata
+                add("/**/*.version")
+                add("/kotlin-tooling-metadata.json")
+                // Kotlin debugging (https://github.com/Kotlin/kotlinx.coroutines/issues/2274)
+                add("/DebugProbesKt.bin")
+            }
+        }
+    }
+
+    packagingOptions {
+        resources {
+            // Reflection symbol list (https://stackoverflow.com/a/41073782/13964629)
+            excludes += "/**/*.kotlin_builtins"
+
+            // okhttp3 is used by some lib (no cookies so publicsuffixes.gz can be dropped)
+            excludes += "/okhttp3/**"
+        }
+    }
+
     compileOptions {
         sourceCompatibility = JavaVersion.VERSION_11
         targetCompatibility = JavaVersion.VERSION_11

app/proguard-rules.pro

@@ -24,3 +24,29 @@
 
 # @Serializable and @Polymorphic are used at runtime for polymorphic serialization.
 -keepattributes RuntimeVisibleAnnotations,AnnotationDefault
+
+# Serializer for classes with named companion objects are retrieved using `getDeclaredClasses`.
+# If you have any, uncomment and replace classes with those containing named companion objects.
+-keepattributes InnerClasses # Needed for `getDeclaredClasses`.
+#-if @kotlinx.serialization.Serializable class
+#com.xinto.opencord.gateway.io.OpCode, # <-- List serializable classes with named companions.
+#com.xinto.opencord.gateway.io.EventName
+#{
+#    static **$* *;
+#}
+-keepnames class <1>$$serializer { # -keepnames suffices; class is kept when serializer() is kept.
+    static <1>$$serializer INSTANCE;
+}
+
+# Uncomment this to preserve the line number information for
+# debugging stack traces.
+-keepattributes SourceFile,LineNumberTable
+
+# Repackage classes into the top-level.
+-repackageclasses
+
+# Amount of optimization iterations, taken from an SO post
+-optimizationpasses 5
+
+# Broaden access modifiers to increase results during optimization
+-allowaccessmodification

gradle.properties

@@ -7,13 +7,19 @@
 # Specifies the JVM arguments used for the daemon process.
 # The setting is particularly useful for tweaking memory settings.
 org.gradle.jvmargs=-Xmx2048m -Dfile.encoding=UTF-8
+
 # When configured, Gradle will run in incubating parallel mode.
 # This option should only be used with decoupled projects. More details, visit
 # http://www.gradle.org/docs/current/userguide/multi_project_builds.html#sec:decoupled_projects
 # org.gradle.parallel=true
+
 # AndroidX package structure to make it clearer which packages are bundled with the
 # Android operating system, and which are packaged with your app"s APK
 # https://developer.android.com/topic/libraries/support-library/androidx-rn
 android.useAndroidX=true
+
 # Kotlin code style for this project: "official" or "obsolete":
 kotlin.code.style=official
+
+# Enable R8 full mode.
+android.enableR8.fullMode=true