Olena

Olena Ostrozhynska

Ukraine

LinkedIn: [відкрити контакти](див. вище в блоці «контактна інформація»)
Telegram: @shalenaolena
Email: [відкрити контакти](див. вище в блоці «контактна інформація»)

Senior iOS Developer with 10+ years of experience in full-cycle iOS
development, production support, code review, technical research, and
documentation for international English-speaking teams.

Languages:

English — Upper-Intermediate / Professional working proficiency
Ukrainian — Native

Programming languages:

Objective-C, Swift

Frameworks and Tools

iOS Frameworks:
SwiftUI, UIKit, Foundation, HealthKit, watchOS

UI & Layout:
SwiftUI, Auto Layout, Storyboard, XIB, SnapKit, Programmatic UI

Programming & Architecture:
MVVM, VIPER, MVC, Multithreading, Networking, Combine, RxSwift, Protocols & Delegates,
Dependency Injection

Third-Party Libraries & Tools:
CocoaPods, Firebase, Crashlytics, Sendbird, Zendesk

Communication & Integration:
Push Notifications, WebSockets, Bluetooth-connected devices

Testing:
Unit Testing, XCTest, Nimble

Tools / Collaboration:

Jira, Trello, Bugzilla

AI tools:
Claude, ChatGPT (as productivity and research assistants)

Professional Profile:

Skilled in full-cycle development, including estimating tasks, mentoring team members, and
conducting interviews. Experienced in providing ongoing support, managing app distribution,
creating technical documentation, code review, and performing research to enhance product
quality. Experienced working in Agile/Scrum teams.

Professional Experience:

TecSynt Solutions (2016): Guzman y Gomez Application
Contributed to building a food pickup app from scratch using Objective-C.

TBWA\Mobile (2016–2018): Various Apps
Developed multiple applications including an internet shop (clothes), loyalty program, social
network, and health research app (mobile + Apple Watch). Converted projects from Objective-C
to Swift.

EPAM Systems (2018–2019): Trader Application
Developed two apps for traders and their clients. Responsible for gathering user feedback and
optimizing flow. Architecture: VIPER. Payments integration via Stripe. Included unit testing.

Client under NDA (2020): Trading Application
Built a market trends tracking app with WebSockets and a custom charting layer. Architecture:
MVVM. Owned major parts of development and helped deliver the MVP.

Client under NDA (2021): VIR-P (Virtual Printing)
Created a paperless printing app saving recipes to cloud services (Google Drive, Dropbox,
OneDrive). Architecture: MVVM. Led development and presented the MVP.

Techstack (2021): Social Network
Developed a social networking app with Sendbird communications library. Architecture: MVVM.
Conducted focus group testing and presented the MVP.

Pixels Matter (2022): Golf Player Application
Developed iOS features for a golf app using GPS and Bluetooth-connected device data.
Architecture: MVVM. Tested on real devices in the lab.

CyberVision (2022–2025): Health Care Application
Worked on iOS features for a healthcare app connected to a custom fitness band, including UI
flows, data presentation, backend interaction, Sendbird/Zendesk integrations, and collaboration
with backend and embedded teams. Architecture: MVVM. Used SwiftUI and Combine for
reactive UI/data flows.

Careem (2025 – May 2026): Super-App
Contributed to development and maintenance of features in a large-scale consumer super-app.
Evaluated frameworks, prepared technical documentation, wrote unit tests, and participated in
end-to-end testing of new features. Collaborated with product and engineering teams in an
English-speaking environment.