High-impact mobile apps, web platforms, and
backend systems that scale.

Chatify is a robust Kotlin Multiplatform application showcasing a modern local-first architecture, reactive synchronization engine, and polished UI animations.
It is built using Compose Multiplatform for shared UI across Android and iOS, SQLDelight for local persistence, and the MVI (Model-View-Intent) pattern for predictable and scalable state management.

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🎯 Key Features

⚡ Local-First Architecture

Chatify works fully offline by design. Every user action is persisted locally first, ensuring instant UI updates with zero latency, even without an internet connection.

🔄 Robust Sync Strategy

A powerful synchronization engine ensures data consistency between local and remote sources using state flags:

• pendingSync → Data waiting to be synced
• isFailed → Sync failed after retries
• pendingDelete → Soft-deleted items awaiting server confirmation

🧠 MVI Architecture

Implements a clean unidirectional data flow using shared ViewModels across Android and iOS for predictable state handling and easier debugging.

✨ Polished UI Animations

Features a premium Typewriter Effect for assistant responses with a custom warm-up phase (1.2s) that prevents historical messages from re-animating.

🏷️ Automatic Session Naming

Intelligently generates chat titles based on the first user message in a conversation.

🔁 Reactive UI Updates

Built with SQLDelight + Coroutines Flow, ensuring the UI always reflects the latest database state in real time.

🌐 Cross-Platform Networking

Uses a shared Ktor 3 client with type-safe API requests and centralized error handling.

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🏗️ Architecture Overview

Chatify follows a layered architecture designed for scalability, testability, and clean separation of concerns:

• Presentation (MVI) → State, Events, and ViewModel orchestration
• Domain → Business logic, UseCases, and core entities
• Data → Repository layer, SQLDelight database, and Ktor services
• Sync → Platform-specific background synchronization services
• DI → Dependency Injection using Koin

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🔄 Sync & Persistence Engine

Chatify ensures data reliability using a state-driven sync system:

Flag	Purpose	UI Behavior
pendingSync	Data waiting to be synced	Shows as “sending” or “pending”
isFailed	Sync failed after retries	Displays retry error message
pendingDelete	Soft-deleted but not confirmed	Hidden from UI until confirmed

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🎭 Animation Strategy: Typewriter Effect

To deliver a premium chat experience, Chatify uses a typewriter animation system with a smart state-handling mechanism:

• Entry Phase → Waits 1.2s for database stream stabilization
• Seeding Phase → Existing message IDs are marked as “seen”
• Active Phase → Only new assistant messages trigger animation

This prevents historical messages from re-animating on every recomposition.

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🧰 Tech Stack

• UI Framework: Compose Multiplatform (1.10.3)
• Language: Kotlin (2.3.20)
• Database: SQLDelight (2.0.2)
• Networking: Ktor (3.0.1)
• Dependency Injection: Koin (4.2.1)
• Serialization: Kotlinx Serialization
• Concurrency: Kotlin Coroutines & Flow

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🚀 Getting Started

🖥️ Backend

The project includes a Node.js + Express backend:

cd backend
npm install
npm start
🤖 Android
Open project in Android Studio Ladybug+
Run module: :composeApp
🍏 iOS
Open iosApp/iosApp.xcodeproj in Xcode 15+
Or run via Android Studio using Kotlin Multiplatform plugin