android: Update targetSdkVersion to 34, i.e., Android 14

android/app/build.gradle

@@ -240,7 +240,7 @@ dependencies {
 
     implementation fileTree(dir: "libs", include: ["*.jar"])
     //noinspection GradleDynamicVersion
-    implementation "com.facebook.react:react-native:+"  // From node_modules
+    implementation project(':ReactAndroid')
 
     implementation "androidx.swiperefreshlayout:swiperefreshlayout:1.0.0"
 

android/build.gradle

@@ -13,13 +13,16 @@ buildscript {
         // but some testing is required and code changes are often required.
         // See upstream for background and more discussion:
         //   https://medium.com/androiddevelopers/picking-your-compilesdkversion-minsdkversion-targetsdkversion-a098a0341ebd
-        targetSdkVersion = 33
+        targetSdkVersion = 34
 
         // Should be the latest SDK version available.  See upstream recommendation:
         //   https://medium.com/androiddevelopers/picking-your-compilesdkversion-minsdkversion-targetsdkversion-a098a0341ebd
         // What's the latest?  Consult this list:
         //   https://developer.android.com/studio/releases/platforms
         compileSdkVersion = 34
+
+        // Latest NDK 24, for Apple Silicon compatibility.
+        ndkVersion = "24.0.8215888"
     }
     repositories {
         google()
@@ -61,6 +64,15 @@ allprojects {
         mavenCentral()
         google()
     }
+
+    configurations.all {
+        resolutionStrategy {
+            dependencySubstitution {
+                // Make our dependencies look at our RN fork built from source.
+                substitute module("com.facebook.react:react-native:+") with project(":ReactAndroid")
+            }
+        }
+    }
 }
 
 subprojects {

android/gradle.properties

@@ -13,7 +13,7 @@
 #   -XX:MaxMetaspaceSize=256m -XX:+HeapDumpOnOutOfMemoryError -Xms256m -Xmx512m
 # We allow more space (no MaxMetaspaceSize; bigger -Xmx),
 # and don't litter heap dumps if that still proves insufficient.
-org.gradle.jvmargs=-Xms256m -Xmx1280m
+org.gradle.jvmargs=-Xms256m -Xmx2048m
 
 # When configured, Gradle will run in incubating parallel mode.
 # This option should only be used with decoupled projects. More details, visit

android/settings.gradle

@@ -1,3 +1,11 @@
+pluginManagement {
+    repositories {
+        gradlePluginPortal()
+        mavenLocal()
+        google()
+    }
+}
+
 rootProject.name = 'ZulipMobile'
 
 apply from: '../node_modules/expo/scripts/autolinking.gradle'
@@ -7,3 +15,11 @@ apply from: file("../node_modules/@react-native-community/cli-platform-android/n
 applyNativeModulesSettingsGradle(settings)
 
 include ':app'
+
+include ':ReactAndroid'
+project(':ReactAndroid').projectDir = new File(
+    rootProject.projectDir, '../node_modules/react-native/ReactAndroid')
+
+// The RN Gradle Plugin is needed to build RN from source.
+// (We do that to make some changes to RN, with our zulip/react-native fork.)
+includeBuild('../node_modules/react-native/packages/react-native-gradle-plugin')

docs/howto/forked-rn.md

@@ -0,0 +1,24 @@
+# Using a `react-native` with cherry-picked or custom changes
+
+Since 2024-09, we use a fork of `react-native` to make changes
+atop 0.68.7. We prefer to avoid upgrading to later `react-native`
+releases because it's laborious and we're eager to retire this
+codebase and transition to `zulip-flutter`.
+
+When there's an issue in React Native that calls for changes in
+React Native:
+
+- Push those changes to our RN fork, `zulip/react-native`,
+  on the `0.68.7-zulip` branch.
+
+- Update the `package.json`:
+
+  ```json
+  "react-native": "zulip/react-native#<commit-id>",
+  ```
+
+- Run `yarn`.
+
+When building for Android, it will take longer the first time because
+React Native is built from source. (`react-native` releases on NPM,
+which we've been using until recently, come with a pre-built binary.)

ios/Podfile.lock

@@ -599,7 +599,7 @@ SPEC CHECKSUMS:
   EXScreenOrientation: e3c072fb0add472a3037482ea43ccbade9b88a25
   EXSQLite: 2b9accd925438293f9f39e0a57a08cca13bdffb2
   FBLazyVector: 63b89dc85804d5817261f56dc4cfb43a9b6d57f5
-  FBReactNativeSpec: 1fa200a9862d9369a53b6fddbbfcdc22bab24062
+  FBReactNativeSpec: de66c1e28c6823a30a53b51dd933560edb24ed3f
   fmt: ff9d55029c625d3757ed641535fd4a75fedc7ce9
   glog: 476ee3e89abb49e07f822b48323c51c57124b572
   RCT-Folly: 4d8508a426467c48885f1151029bc15fa5d7b3b8

package.json

@@ -57,7 +57,7 @@
     "lodash.uniq": "^4.5.0",
     "react": "17.0.2",
     "react-intl": "5.24.6",
-    "react-native": "0.68.7",
+    "react-native": "zulip/react-native#b7b2f6c22",
     "react-native-document-picker": "^8.1.3",
     "react-native-gesture-handler": "^2.8.0",
     "react-native-image-picker": "^5.3.1",