Bachelor's degree in Computer Science, Software Engineering, or a related discipline
Engineer: 1-3+ years of experience; Senior Engineer: 3-5+ years
Solid production experience in Android development (Kotlin and/or Java)
Good understanding of Android SDK, Jetpack components, asynchronous programming, and modern client-side architecture
Required: ability to use AI-powered development tools (Cursor, GitHub Copilot, ChatGPT, Claude, or similar) for cross-stack frontend development
Able to read, understand, debug, and make reasonable changes in iOS or Web codebases with AI tool support
Familiarity with WebSocket, MQTT, gRPC, or similar real-time communication protocols
Understanding of messaging concepts: message delivery, read status, sync, local persistence, offline support, push notifications
Good understanding of client-side performance optimization, memory management, multithreading, and security best practices
Familiar with Git, CI/CD pipelines, automated testing, and Agile processes
Strong debugging, problem-solving, ownership, and communication skills
Experience building IM products or communication platforms (WhatsApp, Telegram, WeChat, Discord, Slack, Messenger, etc.)
iOS development experience (Swift, SwiftUI, Objective-C)
Web frontend experience (TypeScript, React, Vue, Next.js)
Cross-platform client or mobile full-stack development experience
End-to-end encryption, message security, or cryptographic protocols experience
Voice/video calling or RTC technologies experience
Large-scale distributed messaging infrastructure experience
Fintech, payments, or Web3 applications experience
Open-source contributions or published apps on Google Play/App Store