Andrzej Chmielewski, Software Developer in Wrocław, Poland
Andrzej Chmielewski

Software Developer in Wrocław, Poland

Member since August 13, 2016
Andrzej is a highly motivated Android developer trying to be best at what he does. He is constantly learning new things and looking for more opportunities to grow his skills. He tries not to overcomplicate problems, keeping in mind that the code he writes is like a publication: It must be understandable and easy to read to as many people as possible. He's a big proponent of clean code and clean architecture. He's a UX-first thinker.
Andrzej is now available for hire




Wrocław, Poland



Preferred Environment

MacOS, GitHub, Git, Android Studio, IntelliJ

The most amazing...

...thing I've experienced is being featured twice on for articles and open source libraries I've created.


  • Mobile Developer (Android + iOS)

    2018 - PRESENT
    Ease (formely EaseCentral)
    • Wrote an Android app from scratch based on the existing iOS version. (Kotlin).
    • Refactored the entire iOS application to incorporate clean architecture paradigms and clean code (Swift).
    • Introduced instrumented tests for both Android and iOS using Espresso (Android) and EarlGrey + XCUITest (iOS).
    • Integrated Fastlane for iOS and Android project to help build a working continuous integration solution.
    • Introduced unit tests for both Android and iOS applications.
    • Built custom Gradle scripts to allow easier execution for the continuous integration pipeline of Android app.
    Technologies: Mobile, Android SDK, Android Testing, Android, iOS, Swift, Kotlin
  • Flutter Developer

    2020 - 2020
    Vid, Inc. (via Toptal)
    • Created video processing functionalities in Flutter, targetting both iOS and Android. Video processing included: Encoding videos, trimming, and applying separate audio streams from the audio files.
    • Introduced new functionalities into the Flutter project as well as existing ones, making sure all of them work well on both iOS and Android.
    • Helped the team to promptly deliver the Android counterpart written in Flutter based on the existing iOS native app.
    Technologies: Mobile, Video & Audio Processing, Video Processing, iOS, Android, Videos, Flutter
  • Flutter Developer

    2020 - 2020
    Juno Digital Pte., Ltd. (via Toptal)
    • Created a lottery results app in Flutter from scratch for both Android and iOS.
    • Created store listing on Google Play and App store and conducted the release process.
    • Added crash reporting functionalities (Crashlytics) to the Flutter project and monitored the app's performance and health in order to prevent bad user experience.
    Technologies: Mobile, iOS, Android, Flutter
  • Android Developer

    2019 - 2020
    Dubsmash (via Toptal)
    • Introduced new features in a video social media app with over 100 million downloads.
    • Participated in a mature and well-organized scrum process.
    • Helped with the transition of the Java source code into Kotlin.
    • Helped with the redesign of the outdated user interface.
    • Augmented the current continuous integration setup with custom scripts that automated tedious, repetitive tasks.
    Technologies: Mobile, Android SDK, Android Testing, GraphQL, Kotlin, Android
  • Full-stack Android Developer

    2019 - 2019
    Johnson Lab & Supply (via Toptal)
    • Created an Android app that allows field workers to log their work as well as upload photos and record their exact GPS location.
    • Created an admin panel within the app that requires authentication and authorization. It allows the manager to manage projects and employees as well as export all collected data to be viewable on the PC.
    • Designed a Firebase database and optimized it for bandwidth usage as well as keeping the data structure as flat as possible.
    • Introdued Firestore storage service to allow users to upload files that are referenced in the database and allows for assigning files to certain work items.
    • Introduced Firebase Authentication to allow managers to authenticate when logging into the admin panel.
    Technologies: Cloud Firestore, Mobile, Android SDK, GPS, Firebase Authentication, Firebase Realtime Database, Firebase, Kotlin, Android
  • Senior Android Developer

    2017 - 2018
    Disney Streaming Services
    • Helped build an Android SDK for core functionalities within client apps in an organization such as authentication, media streaming, and HTTP API communication layer.
    • Maintained and improved Gradle quality plugins related to unit testing and code coverage.
    • Improved the architecture of the SDK to improve testability and mocking for client apps.
    Technologies: Mobile, Android SDK, Android Testing, Kotlin, Android
  • Android Engineer

    2017 - 2018
    Max2 (via Toptal)
    • Maintained and added new features to an enterprise application for business where venue owners can mange their premises, staff, and client relations.
    • Took care of the continuous integration environment by making sure it is paired up with the code review process.
    • Advised a client with Android-specific decisions about design.
    Technologies: Mobile, Android SDK, Android Testing, Bluetooth, Kotlin, Java, Android
  • Senior Android Developer

    2016 - 2017
    • Introduced CI/CD into the project.
    • Helped junior developers understand clean architecture and clean code principles.
    • Worked on an Android project for a media industry client from the US.
    • Advised the client about possible solutions for certain problems.
    • Helped the design team provide designs adhering to material design principles.
    Technologies: Cloud Firestore, Mobile, Android SDK, Android Testing, Kotlin, Clean Architecture, Espresso, JUnit, Jira, Jenkins, Java, Android
  • Lead Android Developer

    2016 - 2016
    X8 Digital Studio
    • Created an Android app for an enterprise client from the UK that helps with networking during different conferences and meetups.
    • Maintained different smaller Android apps within the company.
    • Introduced CI/CD for all projects being maintained.
    • Worked closely and directly with the clients to identify their needs and suggest optimal solutions.
    • Refactored apps to work with clean architecture.
    • Incorporated clean code principles into new projects.
    Technologies: Mobile, Android SDK, Android Testing, Espresso, CircleCI, Git, JUnit, Jenkins, Java, Android
  • Senior Android Developer

    2013 - 2016
    Ceneo sp. z o.o.
    • Led the Android development team, which consisted of three people.
    • Designed architecture and implemented an Android app for the biggest price comparison company in Poland.
    • Introduced CI/CD with Atlassian's Bamboo.
    • Wrote UI and unit tests.
    • Helped the product owner to identify user needs and plan new features.
    • Guided and taught new Android developers' best practices.
    • Worked with an MVP (Model-view Presenter) pattern.
    Technologies: Mobile, Android SDK, Android Testing, Jira, Espresso, JUnit, Bamboo, Jenkins, Java, Android



  • Languages

    Kotlin, Java, JavaScript, Swift, GraphQL, TypeScript, Objective-C, Python
  • Frameworks

    Flutter, Dagger 2, Android SDK, JUnit, Espresso Testing Framework, Robolectric, Express.js, Swinject
  • Libraries/APIs

    Firebase Android SDK, Retrofit, RxJava, Picasso, REST APIs, Mixpanel Android API, React, Alamofire, Node.js, Chai
  • Tools

    Jira, Android Studio, Crashlytics, Jenkins, CircleCI, Firebase Cloud Messaging (FCM), Bamboo, Fastlane, Xcode, Firebase Test Lab, Firebase Authentication, Gradle, Google Analytics, Maven, OneSignal, TeamCity, Mocha, Git, GitHub, Trello,, IntelliJ
  • Paradigms

    Model View Presenter (MVP), Test-driven Development (TDD), Scrum, Clean Architecture, Clean Code
  • Platforms

    Mobile, Firebase, Android, iOS, Mixpanel, MacOS, Arduino
  • Other

    Android Testing, OkHttp, Scrum Master, EventBus, Firebase Cloud Functions, 3D Printing, 3D Print Design, ESP8266, ESP32, Espresso, Bluetooth, Videos, Video Processing, Video & Audio Processing, GPS, Axios
  • Storage

    Realm, SQLite, NoSQL, Firebase Realtime Database, Cloud Firestore


  • Master's Degree in Computer Science
    2009 - 2014
    Wroclaw Univeristy of Technology - Wroclaw, Poland


  • React Academy
    Toptal, LLC
  • Oracle Certified Associate, Java SE 7 Programmer
  • Professional Scrum Master I

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