Oleksandr Tsvietkov

I am Alexandr Tsvetkov, a dedicated and highly skilled Senior Android Developer with over 15 years of experience, specializing in roles as a Mobile Software Architect and Mobile Team Leader. I excel in delivering robust, high-performance mobile solutions and possess the critical skill set for managing projects across the entire development spectrum.

Core Development Philosophy & Expertise

I am equally proficient in greenfield development—defining the architecture and building complex applications from scratch—and in conducting rapid, high-quality refactoring of existing, unmaintained, or poor-quality codebases. My expertise lies in quickly taking ownership of outdated multi-module applications, selecting modern libraries, and adapting them to contemporary build systems for efficient modernization. I am comfortable working with challenging legacy code and always prioritize efficiency and quality.

Key Technologies

• Languages & Core Frameworks: Kotlin, Java, Android SDK, NDK, AOSP.
• Modern Android Stack: Jetpack (Compose, Live Data, Coroutines, Room, Navigation Component), Koin, Dagger 2/Hilt, Data Binding.
• Architecture & Utilities: MVC/MVP/MVVM, Cicerone, AutoValue, Leakcanary, Firebase (Analytics, Crashlytics), Google ML Kit.
• Networking & Async: Retrofit, Moshi, Gson, RxAndroid/RxJava, Asmack, Socket.IO, Mediasoup (for real-time video/audio).
• Graphics & Multimedia: OpenGL ES (used for financial data visualization), AndEngine, Glide, Picasso, Video transcoding, Camera2.
• Hardware & Security: NFC, BTLE, AES, Face recognitions, Fingerprints, Barcode scanner, DRM.

My Projects

I actively develop and maintain my own advanced applications and libraries:

• The Weather and Wardrobe Assistant: This is a highly complex, nine-month development effort where I served in all project roles. This intelligent app is based on scientific calculations of clothing thermal resistance and heat dissipation, using the user's specific body type and activity level (e.g., standing versus carrying loads) to provide precise, personalized outfit recommendations. 
• TAO Logger (Android Library): A lightweight, informative logger that automatically generates tags including the file name, method, and line number. It provides clickable links in LogCat for quick code navigation.
• TAO Bubbles (Jetpack Compose Library): A lightweight library for displaying customizable "bubbles" or "showcases" that point to specific UI elements for tutorials or feature highlights.
• TAO NFC SDK: A library that simplifies Near Field Communication interactions in Android, providing a higher-level abstraction for easier reading, writing, and management of NFC tags.

Domain Expertise 

My contract work spans critical and specialized industries, providing a broad base of domain knowledge:

• Fintech & Mobile Security: Developed application systems for personal finance management across multiple builds for different international bank clients, and built advanced mobile security libraries and apps for European financial institutions.
• Supply Chain & Blockchain: Implemented solutions for data modeling, registration, and verification of asset identities against the blockchain for logistics professionals, incorporating NFC and BTLE technology.
• Real-Time & Communication: Built video conferencing services for educational platforms and developed libraries for real-time visualization of financial data using OpenGL ES for heatmaps.
• Biometrics & Security: Developed applications incorporating face recognition and fingerprint security features, utilizing P2P technology and on-device encryption.
• Hardware & Low-Level: Experienced in NDK/JNI integration (e.g., integrating a C++ video library) and developing Android drivers and graphical editors for specialized printers.
• Consumer & E-commerce: Created high-volume consumer applications for major US restaurant and coffee chains (ordering ahead, delivery, loyalty programs). I have also participated in an AOSP (Android Open Source Project)-based automotive project.

I am actively seeking a challenging Senior Android Developer or Mobile Team Lead role where I can utilize my blend of architectural expertise, legacy code mastery, and proven leadership to deliver top-tier mobile solutions.