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Oleksii Masnyi, Android Developer in Zadar, Croatia
Oleksii Masnyi

Android Developer in Zadar, Croatia

Member since August 6, 2015
Oleksii is an ex-Facebook senior software engineer who's shipped dozens of Android apps for billions of people. Oleksii has experience building products and teams from the ground up as well as getting into a huge legacy codebase, making dramatic performance improvements and aligning the development processes in existing teams. Oleksii combines leading and architectural skills, product vision and passion to testing, design and user experience to make truly awesome products.
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Portfolio

  • Facebook
    Java, Android, SQLite, Kotlin, Dagger 2, Mercurial, Git, A/B Testing...
  • Geneva Chat
    Android, Kotlin, Coroutines, Dagger 2, Retrofit 2, RxJava 2, SQLite...
  • MetaLab
    Android, Flutter, Java, Kotlin, Coroutines, Dart, Python, TensorFlow...

Experience

Location

Zadar, Croatia

Availability

Part-time

Preferred Environment

Git, Gradle, Android Studio, Kotlin, Android SDK, Android, Bluetooth, Java, Coroutines, Firebase

The most amazing...

...solutions I've built are photo annotation tools for WhatsApp which meet performance constraints for billions of Android devices.

Employment

  • Senior Software Engineer

    2021 - 2022
    Facebook
    • Shipped improvements for camera and status at WhatsApp Android for 2+ billion users, which significantly increased privacy and improved user experience.
    • Developed a new version of the media composer, including a new blur pen tool that met performance constraints for billions of Android devices.
    • Implemented performance metrics for one of the core WhatsApp features.
    Technologies: Java, Android, SQLite, Kotlin, Dagger 2, Mercurial, Git, A/B Testing, Performance, User Interface (UI), Espresso, MacOS, OS X, Android SDK, Android Studio, Architecture, API Architecture, Mobile App Development, Technical Leadership, Software Project Management, Unit Testing, JUnit, Continuous Integration (CI), Product Management, UX Wireframes, Mobile, Widgets, Camera SDK, APK, Side-loading, User Experience (UX), Camera2 API, Android Camera App

  • Lead Android Engineer

    2020 - 2021
    Geneva Chat
    • Introduced the Model–View–ViewModel (MVVM) architecture and Kotlin coroutines across the codebase, significantly increasing the testability and stability of the Android app.
    • Refactored the core app components, increasing the velocity of sending and receiving messages by 5x.
    • Led a small development team to follow better engineering practices, code reviews, continuous integration (CI), and testing.
    Technologies: Android, Kotlin, Coroutines, Dagger 2, Retrofit 2, RxJava 2, SQLite, User Interface (UI), Retrofit, Espresso, RxJava, Google Cloud Messaging, Google Material Design, MacOS, OS X, Android SDK, Java, Android Studio, Architecture, API Architecture, Mobile App Development, REST APIs, Technical Leadership, Software Project Management, Unit Testing, JUnit, Continuous Integration (CI), Product Management, UX Wireframes, Mobile, APIs, Widgets, Swift, REST, WSS, APK, Side-loading, User Experience (UX)

  • Senior Android Engineer

    2015 - 2020
    MetaLab
    • Developed an Android app to integrate with robotic hardware using Bluetooth Low Energy.
    • Built an app leveraging ARCore technology to visualize custom 3D models.
    • Used TensorFlow to build and train various machine learning models in making UI predictions.
    • Led the Android team and introduced the MVVM architecture and Kotlin coroutines. Established the best engineering practices to improve testing, code reviews, and CI.
    • Developed the first async/await open source library to leverage Kotlin coroutines for Android.
    Technologies: Android, Flutter, Java, Kotlin, Coroutines, Dart, Python, TensorFlow, RxJava 2, Dagger 2, Bluetooth LE, ARCore, User Interface (UI), Retrofit, Espresso, RxJava, Google Cloud Messaging, Augmented Reality (AR), Google Material Design, MacOS, OS X, Android SDK, Android Studio, Architecture, API Architecture, iOS, Mobile App Development, REST APIs, Technical Leadership, Software Project Management, Unit Testing, JUnit, Continuous Integration (CI), Product Management, UX Wireframes, Mobile, APIs, Widgets, Swift, REST, APK, Side-loading, User Experience (UX)

  • Senior Android Engineer

    2013 - 2015
    Sony
    • Integrated the rich communication services (RCS) chat client protocol into the messaging app.
    • Supported the phone and tablet platform migration on Android Lollipop.
    • Improved various system apps to follow material design guidelines.
    • Created a library to simplify the background work handling with built-in caching.
    • Guided a team on UI, performance, architecture refactoring, and improvements.
    Technologies: Continuous Integration (CI), Code Review, Gradle, Git, Material Design, Android, Java, User Interface (UI), Espresso, Android Wearables, Google Material Design, MacOS, OS X, IntelliJ IDEA, Android SDK, Android Studio, Kotlin, Architecture, API Architecture, Mobile App Development, Technical Leadership, Unit Testing, JUnit, Mobile, APIs, Widgets, APK, Side-loading, User Experience (UX)

  • Android Engineer

    2012 - 2013
    Lohika
    • Refactored a webcam Android app to support various device configurations.
    • Redesigned the UI and improved usability in a webcam Android app.
    • Developed a platform to host JavaScript web apps in a native Android container with built-in support for auto-update, offline mode, and push notification support.
    Technologies: Continuous Integration (CI), Git, Maven, Android, Java, User Interface (UI), JavaScript, MacOS, OS X, IntelliJ IDEA, Android SDK, Android Studio, Architecture, API Architecture, Mobile App Development, REST APIs, Unit Testing, JUnit, Product Management, UX Wireframes, Mobile, APIs, Widgets, REST, APK, Side-loading, User Experience (UX)

  • Android Engineer

    2010 - 2012
    Samsung
    • Developed a TV remote-control Android app with video broadcasting using Android Native Development Kit (NDK) libraries and the Samsung TV SDK.
    • Created an app to intelligently control Bluetooth speakers with an Advanced Audio Distribution Profile (A2DP).
    • Built an app for group drawing and communication using a shared TV screen.
    • Developed an efficient drawing UI from scratch to demo the new TV SDK.
    • Improved the continuous integration process, increasing the app stability and the development process.
    Technologies: Jenkins, Git, Maven, NDK, Android, Java, User Interface (UI), Scala, Android NDK, IntelliJ IDEA, Android SDK, Android Studio, Architecture, API Architecture, Mobile App Development, REST APIs, Technical Leadership, Unit Testing, JUnit, Continuous Integration (CI), Product Management, UX Wireframes, Mobile, APIs, Widgets, REST, APK, Side-loading, User Experience (UX)

  • Java Developer

    2008 - 2010
    MTI
    • Used the IBM WebSphere Business Integration Server for developing integration solutions to connect 10+ legacy enterprise applications, including enterprise resource planning (ERP) and warehouse management systems (WMS).
    • Developed a new integration platform using Apache Karaf.
    • Supported data migration between legacy enterprise systems.
    Technologies: WebSphere, EventBus, Service-oriented Architecture (SOA), Java, SQL, Microsoft SQL Server, Oracle SQL, Unit Testing, JUnit

Experience

  • Paper
    https://github.com/pilgr/Paper

    Paper is a fast and straightforward open-source NoSQL data storage library for Android that lets users save and restore Java objects by using efficient Kryo serialization and handling data structure that changes automatically.

  • AppDialer

    An app that uses intelligent predictive search algorithms to search apps and contacts most efficiently. I'm the creator, UX designer, and sole developer of this app that I've done as a hobby. The app has two keyboard types—T9 and QWERTY.

  • WhatsApp

    WhatsApp allows users to get fast, simple, and secure messaging and calling, available for free on phones worldwide. I was improving the camera, status, and media composer components, increasing user privacy and enhancing the overall user experience.

  • Notenger
    https://play.google.com/store/apps/details?id=name.pilgr.notenger

    Flutter-based notes and reminder app, done in the style of a chat app. I had the original idea and the product's vision and made the development and shipped the app for Android and iOS (now discontinued).

    Notenger leverages the commonly known design of the chat app to make adding notes and setting reminders as effortless as sending a message. Once a reminder is fired, it appears as an incoming message.

Skills

  • Languages

    Java, Kotlin, SQL, Dart, Scala, JavaScript, Python, Swift

  • Frameworks

    Android SDK, JUnit, Flutter, Dagger 2

  • Libraries/APIs

    RxJava 2, Retrofit 2, REST APIs, Retrofit, Camera2 API, NDK, RxJava, TensorFlow, PyTorch

  • Tools

    Android Studio, Gradle, Git, Maven, Mercurial, Jenkins, IntelliJ IDEA, Google Cloud Messaging, Android NDK

  • Paradigms

    Continuous Integration (CI), API Architecture, Unit Testing, REST, Service-oriented Architecture (SOA)

  • Platforms

    MacOS, OS X, Android, Bluetooth LE, Mobile, Firebase, ARCore, WebSphere, iOS

  • Storage

    SQLite, Microsoft SQL Server, Oracle SQL

  • Other

    Code Review, User Interface (UI), Bluetooth, Coroutines, Performance, Architecture, Mobile App Development, Technical Leadership, Software Project Management, Product Management, UX Wireframes, APIs, Widgets, APK, Side-loading, User Experience (UX), Material Design, Google Material Design, Android Wearables, Espresso, A/B Testing, Android Camera App, EventBus, Augmented Reality (AR), Machine Learning, Deep Learning, Camera SDK, WSS

Education

  • Master's Degree in Computer Science
    2000 - 2007
    National Technical University of Ukraine "Kyiv Polytechnic Institute" - Kyiv, Ukraine

Certifications

  • Sequence Models
    APRIL 2018 - PRESENT
    DeepLearning.AI
  • Convolutional Neural Networks
    FEBRUARY 2018 - PRESENT
    DeepLearning.AI
  • Structuring Machine Learning Projects
    FEBRUARY 2018 - PRESENT
    DeepLearning.AI
  • Improving Deep Neural Networks: Hyperparameter Tuning, Regularization, and Optimization
    JANUARY 2018 - PRESENT
    DeepLearning.AI
  • Neural Networks and Deep Learning
    JANUARY 2018 - PRESENT
    DeepLearning.AI

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