callstack · hurali97 · Jul 8, 2026 · Jul 8, 2026 · Jul 8, 2026 · Jul 8, 2026
diff --git a/.changeset/tall-rabbits-love.md b/.changeset/tall-rabbits-love.md
@@ -0,0 +1,8 @@
+---
+'@callstack/react-native-brownfield': minor
+'@callstack/brownfield-navigation': minor
+'@callstack/brownie': minor
+'@callstack/brownfield-cli': minor
+---
+
+feat: support proguard/R8 minification
diff --git a/apps/ExpoApp56/app.json b/apps/ExpoApp56/app.json
@@ -37,12 +37,7 @@
           }
         }
       ],
-      [
-        "@callstack/react-native-brownfield",
-        {
-          "debug": true
-        }
-      ],
+      "@callstack/react-native-brownfield",
       "expo-image",
       "expo-font",
       "expo-web-browser"

diff --git a/apps/ExpoApp56/package.json b/apps/ExpoApp56/package.json
@@ -16,6 +16,23 @@
     "brownfield:package:ios": "brownfield package:ios --scheme BrownfieldLib --configuration Release --use-prebuilt-rn-core --use-prebuilt-expo --verbose",
     "eas:stg": "EXPO_TOKEN=$EAS_TOKEN eas update --channel production --message 'testing 1st stg channel update' --platform ios --environment staging"
   },
+  "brownfield": {
+    "debug": true,
+    "android": {
+      "expo": {
+        "minifyEnabled": false,
+        "extraProguardRules": [
+          "-keep class com.callstack.rnbrownfield.demo.expoapp56.BrownfieldStore { *; }",
+          "-keep class com.callstack.rnbrownfield.demo.expoapp56.BrownfieldStore$Companion { *; }",
+          "-keep class com.callstack.rnbrownfield.demo.expoapp56.User { *; }",
+          "-keep class com.callstack.rnbrownfield.demo.expoapp56.SettingsStore { *; }",
+          "-keep class com.callstack.rnbrownfield.demo.expoapp56.SettingsStore$Companion { *; }",
+          "-keep class com.callstack.rnbrownfield.demo.expoapp56.Theme { *; }",
+          "-keep class com.callstack.nativebrownfieldnavigation.UserType { *; }"
+        ]
+      }
+    }
+  },
   "dependencies": {
     "@callstack/brownfield-navigation": "workspace:^",
     "@callstack/brownie": "workspace:^",

diff --git a/apps/RNApp/android/BrownfieldLib/proguard-rules.pro b/apps/RNApp/android/BrownfieldLib/proguard-rules.pro
@@ -18,4 +18,16 @@
 
 # If you keep the line number information, uncomment this to
 # hide the original source file name.
-#-renamesourcefileattribute SourceFile
+#-renamesourcefileattribute SourceFile
+
+# Public API consumed from the Brownfield AAR.
+-keep class com.rnapp.brownfieldlib.BrownfieldStore { *; }
+-keep class com.rnapp.brownfieldlib.BrownfieldStore$Companion { *; }
+-keep class com.rnapp.brownfieldlib.User { *; }
+-keep class com.rnapp.brownfieldlib.SettingsStore { *; }
+-keep class com.rnapp.brownfieldlib.SettingsStore$Companion { *; }
+-keep class com.rnapp.brownfieldlib.Theme { *; }
+-keep class com.rnapp.brownfieldlib.ReactNativeHostManager { *; }
+
+# Generated API for brownfield-navigation API consumed from the Brownfield AAR
+-keep class com.callstack.nativebrownfieldnavigation.UserType { *; }
diff --git a/docs/docs/docs/api-reference/configuration.mdx b/docs/docs/docs/api-reference/configuration.mdx
@@ -58,6 +58,10 @@ Example:
     "expo": {
       "packageName": "com.example.app",
       "minSdkVersion": 24,
+      "extraProguardRules": [
+        "-keep class com.example.Foo { *; }"
+      ],
+      "minifyEnabled": false,
       "useLocalGradlePlugin": true
     }
   },
@@ -187,6 +191,8 @@ All file-based platform options mirror CLI flags, but they use camelCase propert
 | `android.expo.artifactId`           | `string`  | Maven artifact ID used when publishing the AAR.                                                                                          |
 | `android.expo.version`              | `string`  | Maven version used when publishing the AAR.                                                                                              |
 | `android.expo.useLocalGradlePlugin` | `boolean` | Load the Brownfield Gradle plugin from `node_modules` via `includeBuild` instead of the Maven classpath dependency. Disabled by default. |
+| `android.expo.minifyEnabled`        | `boolean` | Controls `minifyEnabled` for the generated Android library build. Disabled by default.                                                   |
+| `android.expo.extraProguardRules`   | `string[]`| Additional Proguard rules appended to the generated `proguard-rules.pro`.                                                                |
 
 ### iOS keys
 

diff --git a/docs/docs/docs/guides/_meta.json b/docs/docs/docs/guides/_meta.json
@@ -1,5 +1,6 @@
 [
   "guidelines",
+  "minification",
   "troubleshooting",
   {
     "type": "dir",

diff --git a/docs/docs/docs/guides/minification.mdx b/docs/docs/docs/guides/minification.mdx
@@ -0,0 +1,84 @@
+# Minification
+
+This guide shows how to enable minification for both Expo and bare React Native brownfield modules.
+
+## Expo
+
+Configure minification through the Brownfield config in `package.json` and let `expo prebuild` apply it to the generated module.
+
+Steps:
+
+1. Add a `brownfield` block to `package.json` and enable `android.expo.minifyEnabled`.
+2. Add keep rules in `android.expo.extraProguardRules` for generated Brownie store types, navigation types, and host manager classes you need to keep.
+3. Run `expo prebuild` to regenerate the Android module with the new settings.
+
+Example (see [apps/ExpoApp56](https://github.com/callstack/react-native-brownfield/blob/main/apps/ExpoApp56/package.json)):
+
+```json
+{
+  "brownfield": {
+    "debug": true,
+    "android": {
+      "expo": {
+        "minifyEnabled": true,
+        "extraProguardRules": [
+          // If you're using Brownie, add the generated store here
+          "-keep class com.your.expoapp.BrownfieldStore { *; }",
+          "-keep class com.your.expoapp.BrownfieldStore$Companion { *; }",
+          "-keep class com.your.expoapp.User { *; }",
+          "-keep class com.your.expoapp.SettingsStore { *; }",
+          "-keep class com.your.expoapp.SettingsStore$Companion { *; }",
+          "-keep class com.your.expoapp.Theme { *; }",
+
+          // If you're using Brownfield Navigation, add the generated types here
+          "-keep class com.callstack.nativebrownfieldnavigation.UserType { *; }",
+
+          // Any other rule to add
+          //"-keep class ..."
+        ]
+      }
+    }
+  }
+}
+```
+
+## Bare React Native
+
+For bare React Native, you do not need any Brownfield config. Enable minification in the module itself and add Proguard rules manually.
+
+Steps:
+
+1. In your `brownfieldlib/build.gradle.kts`, enable `isMinifyEnabled = true` in the `release` build type.
+2. Ensure `proguard-rules.pro` keeps the generated Brownie store types, navigation types, and your host manager if you have one.
+
+Example (see [apps/RNApp](https://github.com/callstack/react-native-brownfield/blob/main/apps/RNApp/android/app/proguard-rules.pro)):
+
+```kts
+android {
+    buildTypes {
+        release {
+            isMinifyEnabled = true
+            proguardFiles(
+                getDefaultProguardFile("proguard-android-optimize.txt"),
+                "proguard-rules.pro"
+            )
+        }
+    }
+}
+```
+
+```json
+// If you're using Brownie, add the generated store here
+-keep class com.rnapp.brownfieldlib.BrownfieldStore { *; }
+-keep class com.rnapp.brownfieldlib.BrownfieldStore$Companion { *; }
+-keep class com.rnapp.brownfieldlib.User { *; }
+-keep class com.rnapp.brownfieldlib.SettingsStore { *; }
+-keep class com.rnapp.brownfieldlib.SettingsStore$Companion { *; }
+-keep class com.rnapp.brownfieldlib.Theme { *; }
+
+// If you're using Brownfield Navigation, add the generated types here
+-keep class com.callstack.nativebrownfieldnavigation.UserType { *; }
+
+// Any other rule to add
+//"-keep class ..."
+```
diff --git a/packages/brownfield-navigation/android/build.gradle b/packages/brownfield-navigation/android/build.gradle
@@ -40,6 +40,7 @@ android {
   defaultConfig {
     minSdkVersion getExtOrDefault("minSdkVersion")
     targetSdkVersion getExtOrDefault("targetSdkVersion")
+    consumerProguardFiles "consumer-rules.pro"
   }
 
   buildFeatures {

diff --git a/packages/brownfield-navigation/android/consumer-rules.pro b/packages/brownfield-navigation/android/consumer-rules.pro
@@ -0,0 +1,4 @@
+-keep class com.callstack.nativebrownfieldnavigation.NativeBrownfieldNavigationPackage { *; }
+-keep class com.callstack.nativebrownfieldnavigation.NativeBrownfieldNavigationModule { *; }
+-keep interface com.callstack.nativebrownfieldnavigation.BrownfieldNavigationDelegate { *; }
+-keep class com.callstack.nativebrownfieldnavigation.BrownfieldNavigationManager { *; }
diff --git a/packages/brownie/android/consumer-rules.pro b/packages/brownie/android/consumer-rules.pro
@@ -2,3 +2,10 @@
     void onStoreDidChange(java.lang.String);
     native <methods>;
 }
+
+-keep class com.callstack.brownie.Store { *; }
+-keep class com.callstack.brownie.StoreKt { *; }
+-keep class com.callstack.brownie.StoreManager { *; }
+-keep class com.callstack.brownie.StoreManager$Companion { *; }
+-keep class com.callstack.brownie.StoreManagerKt { *; }
+-keep class com.callstack.brownie.BrownieStoreRegistrationKt { *; }
diff --git a/packages/cli/schema.json b/packages/cli/schema.json
@@ -57,6 +57,13 @@
           "description": "Compile SDK version for the Android library.",
           "type": "number"
         },
+        "extraProguardRules": {
+          "description": "Extra Proguard rules appended to the default rules.",
+          "items": {
+            "type": "string"
+          },
+          "type": "array"
+        },
         "groupId": {
           "description": "Maven group ID used when publishing the AAR.",
           "type": "string"
@@ -65,6 +72,10 @@
           "description": "Minimum SDK version for the Android library.",
           "type": "number"
         },
+        "minifyEnabled": {
+          "description": "Toggle minification for the generated Android library.",
+          "type": "boolean"
+        },
         "packageName": {
           "description": "The package name for the Android library module.",
           "type": "string"

diff --git a/packages/cli/src/__tests__/expoPluginConfig.test.ts b/packages/cli/src/__tests__/expoPluginConfig.test.ts
@@ -206,6 +206,8 @@ describe('resolveBrownfieldPluginConfig', () => {
         artifactId: 'brownfieldlib',
         version: '0.0.1-SNAPSHOT',
         useLocalGradlePlugin: false,
+        minifyEnabled: false,
+        extraProguardRules: [],
       },
     });
   });
@@ -309,6 +311,8 @@ describe('resolveBrownfieldPluginConfig', () => {
       moduleName: 'mylib',
       minSdkVersion: 26,
       version: '2.0.0',
+      minifyEnabled: false,
+      extraProguardRules: [],
     });
     expect(resolved.ios).toMatchObject({
       frameworkName: 'MyLib',
@@ -334,6 +338,31 @@ describe('resolveBrownfieldPluginConfig', () => {
     expect(resolved.android?.useLocalGradlePlugin).toBe(true);
   });
 
+  it('maps android.expo.minifyEnabled and extraProguardRules from file config', () => {
+    const resolved = resolveBrownfieldPluginConfig(
+      {},
+      {
+        android: {
+          moduleName: 'mylib',
+          expo: {
+            minifyEnabled: true,
+            extraProguardRules: [
+              '-keep class com.example.Foo { *; }',
+              '-dontwarn com.example.Bar',
+            ],
+          },
+        },
+      },
+      baseExpoConfig
+    );
+
+    expect(resolved.android?.minifyEnabled).toBe(true);
+    expect(resolved.android?.extraProguardRules).toEqual([
+      '-keep class com.example.Foo { *; }',
+      '-dontwarn com.example.Bar',
+    ]);
+  });
+
   it('maps android.useLocalGradlePlugin from legacy app.json plugin props', () => {
     const resolved = resolveBrownfieldPluginConfig(
       {
@@ -348,4 +377,27 @@ describe('resolveBrownfieldPluginConfig', () => {
 
     expect(resolved.android?.useLocalGradlePlugin).toBe(true);
   });
+
+  it('maps android minifyEnabled and extraProguardRules from legacy app.json plugin props', () => {
+    const resolved = resolveBrownfieldPluginConfig(
+      {
+        android: {
+          moduleName: 'mylib',
+          minifyEnabled: true,
+          extraProguardRules: [
+            '-keep class com.example.Legacy { *; }',
+            '-dontwarn com.example.Legacy',
+          ],
+        },
+      },
+      null,
+      baseExpoConfig
+    );
+
+    expect(resolved.android?.minifyEnabled).toBe(true);
+    expect(resolved.android?.extraProguardRules).toEqual([
+      '-keep class com.example.Legacy { *; }',
+      '-dontwarn com.example.Legacy',
+    ]);
+  });
 });
diff --git a/packages/cli/src/expoPluginConfig.ts b/packages/cli/src/expoPluginConfig.ts
@@ -24,6 +24,8 @@ export type BrownfieldPluginProps = {
     artifactId?: string;
     version?: string;
     useLocalGradlePlugin?: boolean;
+    minifyEnabled?: boolean;
+    extraProguardRules?: string[];
   };
 };
 
@@ -37,6 +39,8 @@ export type ResolvedBrownfieldPluginAndroidConfig = {
   artifactId: string;
   version: string;
   useLocalGradlePlugin: boolean;
+  minifyEnabled: boolean;
+  extraProguardRules: string[];
 };
 
 export type ResolvedBrownfieldPluginIosConfig = {
@@ -189,6 +193,8 @@ export function resolveBrownfieldPluginConfig(
           version: effectiveProps.android?.version ?? '0.0.1-SNAPSHOT',
           useLocalGradlePlugin:
             effectiveProps.android?.useLocalGradlePlugin ?? false,
+        minifyEnabled: effectiveProps.android?.minifyEnabled ?? false,
+        extraProguardRules: effectiveProps.android?.extraProguardRules ?? [],
         }
       : null,
   };

diff --git a/packages/cli/src/types.ts b/packages/cli/src/types.ts
@@ -56,6 +56,16 @@ export type BrownfieldExpoAndroidConfig = {
    */
   packageName?: string;
 
+  /**
+   * Toggle minification for the generated Android library.
+   */
+  minifyEnabled?: boolean;
+
+  /**
+   * Extra Proguard rules appended to the default rules.
+   */
+  extraProguardRules?: string[];
+
   /**
    * Minimum SDK version for the Android library.
    */

diff --git a/packages/react-native-brownfield/android/build.gradle b/packages/react-native-brownfield/android/build.gradle
@@ -74,6 +74,7 @@ android {
   defaultConfig {
     minSdkVersion getExtOrIntegerDefault("minSdkVersion")
     targetSdkVersion getExtOrIntegerDefault("targetSdkVersion")
+    consumerProguardFiles "consumer-rules.pro"
     buildConfigField "boolean", "IS_NEW_ARCHITECTURE_ENABLED", isNewArchitectureEnabled().toString()
     buildConfigField "boolean", "IS_HERMES_ENABLED", isHermesEnabled().toString()
     buildConfigField "String", "RN_VERSION", "\"$reactNativeVersion\""

diff --git a/packages/react-native-brownfield/android/consumer-rules.pro b/packages/react-native-brownfield/android/consumer-rules.pro
@@ -0,0 +1,11 @@
+-keep class com.callstack.reactnativebrownfield.ReactNativeBrownfield { *; }
+-keep class com.callstack.reactnativebrownfield.ReactNativeBrownfield$Companion { *; }
+-keep interface com.callstack.reactnativebrownfield.OnJSBundleLoaded { *; }
+-keep interface com.callstack.reactnativebrownfield.OnMessageListener { *; }
+-keep class com.callstack.reactnativebrownfield.ReactNativeFragment { *; }
+-keep class com.callstack.reactnativebrownfield.ReactNativeFragment$Companion { *; }
+-keep class com.callstack.reactnativebrownfield.ReactDelegateWrapper { *; }
+-keep class com.callstack.reactnativebrownfield.ReactNativeBrownfieldPackage { *; }
+-keep class com.callstack.reactnativebrownfield.ReactNativeBrownfieldModule { *; }
+-keep class com.callstack.reactnativebrownfield.constants.ReactNativeFragmentArgNames { *; }
+-keep class com.callstack.reactnativebrownfield.constants.ReactNativeFragmentArgNames$Companion { *; }