Oleksii Tomin, Developer in Calgary, AB, Canada
Oleksii is available for hire
Hire Oleksii

Oleksii Tomin

Verified Expert  in Engineering

Android Engineer and Developer

Calgary, AB, Canada

Toptal member since February 4, 2025

Expertise
JavaKotlinJUnitAndroidAndroid SDKBluetoothGraphQLMathematics
Bio

Oleksii is an experienced native Android developer, well-versed in Android SDK, Kotlin, Java, and Coroutines. With a master's degree in computer mechanics, his technical skills span Jetpack Compose, Dagger, Hilt, RxJava, SQL, Clean Architecture, GraphQL, Retrofit, UX design, Scrum, Git, and unit and UI testing. Oleksii is a master in developing features and solutions to take businesses to the next level.

Portfolio

PayPal
Android SDK, Kotlin, Java, GraphQL, Lighthouse
Payfare
Android SDK, Java, Kotlin, Jetpack Compose, Crashlytics, Coroutines
SOTI
Java, Kotlin, Android SDK, RxJava, Coroutines, Scrum Master

Experience

  • Kotlin - 10 years
  • Android SDK - 8 years
  • Coroutines - 8 years
  • Model View ViewModel (MVVM) - 5 years
  • Model View Intent (MVI) - 5 years
  • Jetpack Compose - 5 years
  • Hilt - 5 years
  • Dagger 2 - 5 years

Availability

Full-time

Preferred Environment

Android Studio, Android

The most amazing...

...solution I've developed is the UberPro Android native client from scratch.

Work Experience

Android Developer

2024 - PRESENT
PayPal
  • Improved unit testing coverage for the PayPal expenses flow from 20% to 80%.
  • Designed three information bottom sheets and provided accessibility standards within the PayPal subscriptions flow.
  • Introduced event tracking with Lighthouse and implemented flows to manage subscriptions.
Technologies: Android SDK, Kotlin, Java, GraphQL, Lighthouse

Android Engineer

2022 - 2024
Payfare
  • Set up and delivered an Uber payments client from scratch using Jetpack Compose.
  • Designed a functionality to display money-spent insights using bar charts and graphics to represent different metrics for the DoorDash payments client.
  • Redesigned and refactored the dashboard for the DoorDash payments client.
  • Migrated the Lyft and DoorDash payments clients to Model View Intent (MVI) architecture from Model View Presenter (MVP). I also replaced RxJava with Kotlin Coroutines.
  • Established a unit tests framework and provided most code coverage for the DoorDash, Lyft, and Uber payments clients, constantly monitoring and fixing bugs using Crashlytics.
Technologies: Android SDK, Java, Kotlin, Jetpack Compose, Crashlytics, Coroutines

Android Developer

2018 - 2022
SOTI
  • Developed features for a JavaScript interpreter module on SOTI MobiControl and built features for the kiosk screen within the SOTI MobiControl project.
  • Created features for the remote control Android native .so library and resolved complex customer support issues.
  • Helped migrate critical codebase from Java to Kotlin, refactored from RxJava to Coroutines, and acted as Scrum Master for a year.
Technologies: Java, Kotlin, Android SDK, RxJava, Coroutines, Scrum Master

Experience

Bluetooth Low Energy (LE) Devices Lookup Tool

https://github.com/o-tomin/jdrf
This project involved creating a tool that scans for Bluetooth LE devices and displays their details. The system allows to read and write values over Bluetooth, and uses Android's Bluetooth LE API, Kotlin, Jetpack Compose, and Hilt. In addition, the tool leverages Material Design and offers dark and light modes.

Education

2010 - 2016

Master's Degree in Computer Mechanics

National Technical University "Kharkiv Polytechnic Institute" - Kharkiv, Ukraine

Skills

Libraries/APIs

RxJava

Tools

Android Studio, Lighthouse, Crashlytics

Languages

Java, Kotlin, GraphQL

Frameworks

Android SDK, Dagger 2, JUnit

Paradigms

Model View Intent (MVI), Model View ViewModel (MVVM), Clean Architecture, Scrum

Platforms

Android, Bluetooth Low Energy (LE)

Other

Programming, Hilt, Jetpack Compose, RecyclerView, Bluetooth, Coroutines, Mathematics, Physics, Philosophy, Material Design, Scrum Master

Collaboration That Works

How to Work with Toptal

Toptal matches you directly with global industry experts from our network in hours—not weeks or months.

1

Share your needs

Discuss your requirements and refine your scope in a call with a Toptal domain expert.
2

Choose your talent

Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.
3

Start your risk-free talent trial

Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hire them.

Top talent is in high demand.

Start hiring