Oleksandr Andreichuk
Verified Expert in Engineering
Software Developer
Lviv, Lviv Oblast, Ukraine
Toptal member since November 12, 2021
Oleksandr is a software engineer with extensive experience in native and cross-platform app development. He is skilled in native iOS, Android, macOS, Windows, and cross-platform mobile frameworks like Xamarin Native, Xamarin.Forms, and Flutter. Cross-platform and native development knowledge enables Oleksandr to perform a broad spectrum of work and create beautiful, fully functional applications for multiple platforms.
Portfolio
Experience
- iOS - 10 years
- Android - 10 years
- C# - 10 years
- Mobile - 10 years
- Desktop - 10 years
- .NET - 10 years
- Xamarin - 7 years
- Windows Presentation Foundation (WPF) - 5 years
Preferred Environment
Visual Studio, Git, Visual Studio Code (VS Code), JetBrains Rider, Xcode, Android Studio
The most amazing...
...contribution I've given is for the Xamarin.Forms project that is used by thousands of people.
Work Experience
Windows App Developer
Toggl
- Rectified memory leaks, resulting in a significant reduction in memory pressure for larger workplaces.
- Resolved major synchronization issues caused by race conditions.
- Implemented a variety of feature requests and bug fixes after the initial beta release.
Mobile App Developer
easierLife
- Developed cross-platform SDK push notifications with offline message delivery handling.
- Implemented an auto-generated networking layer based on OpenAPI specifications.
- Developed an independent watchOS app built using Swift, SwiftUI, and Combine.
- Built a unit and integration test suite for handling regressions.
Mobile App Developer
eKidz
- Implemented virtual classroom support for students and teachers.
- Implemented audio recording for students and audio analysis for teachers.
- Improved offline mode handling by introducing a performant caching layer.
- Improved feature performance by more than 70% using more performant algorithms and data structures.
Mobile App Developer
Mapcite
- Converted native apps on iOS and Android platforms to Xamarin.Forms.
- Implemented background location changes monitoring and geofence detection.
- Implemented an augmented reality browser with points of interest location.
Mobile App Developer
OfficeLynq
- Implemented indoor position tracking functionality.
- Implemented wireless Bluetooth low energy (BLE) devices firmware updates.
- Improved BLE beacon ranging and monitoring reliability.
Cross-Platform App Developer
Dauntless Software
- Developed a cross-platform framework for Android, iOS, Windows, macOS, and UWP apps that allowed the company to quickly build apps for all major platforms using a single codebase.
- Migrated legacy native macOS/iOS (Objective-C), Android (Java), and PC (VB6) apps to the new cross-platform framework.
- Created automated build scripts for building over 30 titles of the app for different platforms.
- Implemented an internal crash reporting system that sends crash reports immediately and allows to check the apps' health and fix issues before any user complains.
Experience
Pilot Logbook Application
Smart Office Application
Language Development Application
Education
Master's Degree in Computer Engineering
Lviv Polytechnic National University - Lviv, Ukraine
Skills
Libraries/APIs
Xamarin.iOS, Xamarin.Android, ReactiveX
Tools
Visual Studio, HealhKit, Git, JetBrains Rider, Xcode, Android Studio
Platforms
Xamarin, iOS, Android, Windows, MacOS, Visual Studio Code (VS Code), Desktop, Mobile, Bluetooth Low Energy (LE), Win32
Frameworks
.NET, Windows Presentation Foundation (WPF), Flutter, Cocoa, ASP.NET Core, StoreKit, Entity Framework Core
Languages
Java, Objective-C, C#, Swift, Kotlin, F#, JavaScript, CSS, HTML
Paradigms
Functional Programming, Object-oriented Programming (OOP)
Storage
SQLite
Other
Algorithms, Data Structures, Xamarin.Forms, Augmented Reality (AR), Location Tracking, Maps, Geofencing, Bluetooth Beacons, Device Firmware Updates (DFU), iOS Animations, Android Animations, Custom Views, Offline Data Synchronization, Audio Recording, SVG
How to Work with Toptal
Toptal matches you directly with global industry experts from our network in hours—not weeks or months.
Share your needs
Choose your talent
Start your risk-free talent trial
Top talent is in high demand.
Start hiring