Money Generator App - Kotlin Multiplatform

This application has been converted to Kotlin Multiplatform with Compose Multiplatform for native Android and iOS builds.

What Changed

This project was migrated from React Native (TypeScript/JavaScript) to Kotlin Native (pure Kotlin multiplatform). Key changes include:

Before (React Native)

• UI Framework: React Native with TypeScript
• Build: Metro bundler + React Native CLI
• Runtime: JavaScript bridge to native modules
• Platform Support: Android & iOS via React Native

After (Kotlin Native)

• UI Framework: Compose Multiplatform (Kotlin)
• Build: Gradle with Kotlin Native compiler
• Runtime: Compiled to native machine code (no bridge)
• Platform Support: Android & iOS via Kotlin Native

Architecture

The project uses a Kotlin Multiplatform structure:

MoneyGeneratorApp/
├── composeApp/              # Shared library module
│   ├── src/
│   │   ├── commonMain/      # Shared UI and business logic
│   │   ├── androidMain/     # Android-specific code
│   │   └── iosMain/         # iOS-specific code
│   └── build.gradle.kts
│
├── androidApp/              # Android application module
│   └── build.gradle.kts
│
├── build.gradle.kts         # Root build configuration
└── settings.gradle.kts      # Project modules

Prerequisites

• JDK 17 or higher
• Kotlin 2.1.20
• Android SDK with:
  • Compile SDK: 36
  • Min SDK: 24
  • Target SDK: 36
  • Build Tools: 36.0.0
• Gradle 9.0.0 (via wrapper)

For iOS builds (macOS only):

• Xcode 15.0+
• CocoaPods

Building the Application

Android

Debug Build

./gradlew :androidApp:assembleDebug

Output: androidApp/build/outputs/apk/debug/androidApp-debug.apk

Release Build

./gradlew :androidApp:assembleRelease

Output: androidApp/build/outputs/apk/release/androidApp-release.apk

Install to Device/Emulator

./gradlew :androidApp:installDebug

iOS (macOS only)

Build Framework

./gradlew :composeApp:linkDebugFrameworkIosSimulatorArm64

For physical devices:

./gradlew :composeApp:linkReleaseFrameworkIosArm64

Technology Stack

• Kotlin 2.1.20: Programming language for all platforms
• Compose Multiplatform 1.8.1: Cross-platform UI framework
• Material 3: Modern design system
• Kotlin Native: Native compilation for iOS
• Android Gradle Plugin 8.5.2: Build system

Key Features

• Single Codebase: Shared UI and business logic across platforms
• Native Performance: Compiled to machine code (no JavaScript bridge)
• Modern UI: Compose Multiplatform with Material 3
• Type Safety: Full Kotlin type system across all code

Application Features

The Money Generator app provides:

• Job Boards: Categorized job listings (Local Missions, Digital Services, Shift-Based Ops)
• Smart Workflows: Delivery Mode, Freelance Mode, Support Mode
• Financial Stack: Liquidity, Benefits, Expense Intelligence
• Integration Hub: Unified API Gateway and White-Label Marketplace
• Master Key Architecture: Secure routing and billing
• Monetization Engine: Subscriptions, cost-plus billing, commissions
• Compliance: Enterprise-grade security and audit trails
• Roadmap: MVP → Scale → Enterprise phases

Development

Clean Build

./gradlew clean

Build All Modules

./gradlew build

List Available Tasks

./gradlew tasks

Migration Notes

The TypeScript/React UI has been fully ported to Kotlin Compose:

• React Components → @Composable functions
• StyleSheet → Modifier chains
• useState/useEffect → remember/LaunchedEffect
• Props → Function parameters
• Type definitions → data classes

All business logic, data models, and UI styling have been preserved in the conversion.

Troubleshooting

Gradle Sync Failures

./gradlew --stop
rm -rf ~/.gradle/caches/
./gradlew build --refresh-dependencies

Android SDK Issues

Ensure correct SDK versions in Android Studio:

• SDK Platform 36
• Build Tools 36.0.0

Network/Repository Issues

If Maven repositories are unavailable:

./gradlew build --offline

Additional Documentation

See README_KOTLIN_NATIVE.md for detailed Kotlin Native build instructions.

See README_REACT_NATIVE.md.backup for the original React Native documentation (deprecated).

See BUILD_INSTRUCTIONS.md for the original React Native build documentation (deprecated).

License

• React Native Website - learn more about React Native.
• Getting Started - an overview of React Native and how setup your environment.
• Learn the Basics - a guided tour of the React Native basics.
• Blog - read the latest official React Native Blog posts.
• @facebook/react-native - the Open Source; GitHub repository for React Native.

Backend (Express + integrations)

We ship a minimal backend under /server to keep secrets off-device and centralize integrations.

Setup

1. Copy .env.example to .env and fill in PayPal/Plaid secrets (only on the backend).
2. Install server deps: npm install --prefix server.
3. Start the API: npm run dev --prefix server (default port 4000).

Local webhook testing

• Use a tunneling tool (e.g., ngrok) pointing at localhost:4000. Configure the public URL in PayPal/Plaid console.
• Webhooks are signed (HMAC-SHA256) and idempotent. Duplicate ids will return status: duplicate.
• Correlation IDs and structured logs are emitted for every request; metrics counters available at /health.

Tests

• Unit tests for webhook signature verification + idempotency: npm test --prefix server.

PayPal webhook setup

• Point PayPal webhooks to /webhooks/paypal.
• Configure PAYPAL_WEBHOOK_SECRET in .env to match your PayPal app.
• Subscription flows use backend-only endpoints:
  • POST /billing/paypal/subscription/create -> returns approvalUrl + providerSubscriptionId.
  • After user approval, call POST /billing/paypal/subscription/confirm to activate and grant entitlements.
  • POST /billing/paypal/subscription/cancel to terminate.
• Webhooks are idempotent and state transitions are validated server-side; outbound CRM webhooks are queued with retries. See LICENSE file for details.