Domagoj is available for hire
Hire DomagojDomagoj Stanković
Verified Expert in Engineering
Xcode Developer
Zagreb, Croatia
Toptal member since January 8, 2019
Bio
As a mobile architect specializing in iOS and Flutter, Domagoj is deeply committed to crafting well-structured, efficient, and testable code. With extensive knowledge in Swift, Objective-C, and Dart, he has successfully completed a broad range of projects, spanning from fast-growing startups to established giants like Facebook. In his proactive role, Domagoj actively contributes to product development, efficiently identifying and resolving high-risk items.
Portfolio
Underflow
Viper, Model View ViewModel (MVVM), RxSwift, Objective-C, Swift, iOS...
Cached
iOS, Swift, SwiftUI, Firebase, Swift 5, Firebase Authentication
Mariko
Flutter, Dart, Firebase, FlutterFlow
Experience
- Xcode - 9 years
- iOS - 9 years
- Swift - 7 years
- Unit Testing - 6 years
- Firebase - 4 years
- Objective-C - 4 years
- RxSwift - 3 years
- SwiftUI - 2 years
Preferred Environment
Git, Xcode, Objective-C, Swift, iOS, RxSwift, VIPER Architecture, Flutter, Dart
The most amazing...
...thing I've built is a platform-independent app that wraps an existing C++ framework, reliably running numerous evolutionary computation experiments in parallel.
Work Experience
CEO | Founder | iOS Development Consultant
2020 - PRESENT
Underflow
- Consulted companies regarding app development and project management.
- Set up architecture and processes for iOS development. Adapted a React Native app for iOS.
- Helped integrate a low-level GPU library into an Xcode project.
- Built custom apps for clients in Flutter and FlutterFlow.
Technologies: Viper, Model View ViewModel (MVVM), RxSwift, Objective-C, Swift, iOS, Mobile Development, Object-oriented Programming (OOP), Slack, Mobile, iOS SDK, iOS Native Libraries, Flutter, Dart
Senior iOS Engineer
2023 - 2024
Cached
- Developed and successfully launched an engaging iOS app for data collection, incorporating captivating gamification features while adhering to a demanding timeframe.
- Utilized SwiftUI and Swift concurrency to design and build a modern, responsive, and efficient user interface.
- Used Firebase Authentication with multi-factor authentication and Firestore to develop robust and secure authentication and data storage.
- Implemented Persona for reliable KYC verification.
- Integrated MX for a streamlined user remuneration process.
- Implemented Magic Link integration to establish a secure and user-friendly Web3 wallet solution.
Technologies: iOS, Swift, SwiftUI, Firebase, Swift 5, Firebase Authentication
Flutter Developer
2023 - 2023
Mariko
- Developed a specialized To-Do application tailored for individuals with autism.
- Built an iOS, Android, and web app using FlutterFlow and Flutter.
- Used Firebase Auth for authentication and Firestore for data storage.
Technologies: Flutter, Dart, Firebase, FlutterFlow
Mobile Architect | Senior Product Engineer
2021 - 2023
Bunch
- Delivered a rewrite of the app using RxSwift and VIPER architecture, significantly contributing to closing the $1.5 million fundraising round.
- Maintained and fixed bugs in legacy apps written in SwiftUI and Combine.
- Contributed proactively to product development, ensuring that high-risk items got flagged and resolved promptly. Wrote behavioral and technical documentation and broke down product requirements into tickets.
- Integrated fastlane with CircleCI to achieve continuous integration. Cleaned up after a CircleCI security incident and moved to GitHub Actions.
- Built in-app purchases using RevenueCat and paywalls using Superwall. Integrated Sentry and Crashlytics for error and crash logging. Displayed video and audio content in the app using AVFoundation.
- Used Amplitude and Segment to investigate user journeys and monitor important KPIs. Shipped features and controlled them using LaunchDarkly feature flags.
- Wrote hundreds of unit and snapshot tests to increase stability and confidence when releasing.
- Adopted the Shape Up methodology to accelerate product development.
- Built an Android app from scratch in Flutter using the Provider state management approach.
Technologies: Swift, RxSwift, VIPER Architecture, Git, SnapKit, CocoaPods, Xcode, CircleCI, Sentry, Fastlane, UIKit, Amplitude, Segment, Braze, Firebase, Airtable, Unit Testing, LaunchDarkly, iOS Instruments, SwiftLint, Jira, Test-driven Development (TDD), Object-oriented Programming (OOP), XCTest, Slack, Alamofire, Continuous Integration (CI), Viper, Bash Script, Mobile Development, SwiftUI, AVFoundation, iOS Video, Figma, Mobile App Development, Mobile App Design, REST, APIs, Architecture, CI/CD Pipelines, Mobile, iOS SDK, iOS Native Libraries, iOS Frameworks, iOS API, Flutter, Dart
iOS Development Consultant
2021 - 2021
LipSurf
- Created a speech recognition library in Swift that uses the Speech framework.
- Integrated Swift library into a React Native code.
- Ensured that speech recognition calls were thread-safe and robust.
Technologies: iOS, Objective-C, Swift, React Native Bridge, React Native, Speech Recognition, Multithreading, Mobile, iOS Native Libraries
Senior Software Engineer
2020 - 2021
Sportening
- Created a rich UI with smooth animations and interactive custom components.
- Built a robust and responsive app using RxSwift and clean architecture.
- Wrote hundreds of unit tests using snapshot testing, RxBlocking, and RxTest.
- Wrote several bash scripts to record network traffic smartly. Also wrote scripts to automate tedious tasks like updating proto models, downloading and formatting localization files, and more.
- Moved the codebase from Carthage to Swift Package Manager.
Technologies: Swift, iOS, RxSwift, Clean Architecture, Protobuf, UIKit, Unit Testing, Bash Script, Jira, Confluence, Carthage, iOS Instruments, SwiftLint, Object-oriented Programming (OOP), XCTest, Slack, Alamofire, Core Data, Mobile Development, Amplitude, Figma, Mobile App Development, Mobile App Design, REST, APIs, Real-time Data, Mobile, iOS SDK, iOS Native Libraries, Algorithms, iOS Frameworks, iOS API
iOS Development Consultant
2020 - 2020
Farm Credit DRP
- Boosted the development of an iPhone insurance app.
- Delivered all requirements on time, following a tight schedule.
- Built a reactive application using RxSwift and MVVM.
Technologies: Model View ViewModel (MVVM), RxSwift, Swift, iOS, Mobile Development, Object-oriented Programming (OOP), Mobile, iOS SDK, iOS Native Libraries, iOS API, iOS Frameworks
Senior iOS Developer
2019 - 2020
Nomadic Tribe
- Developed a booking system and integrated it with Stripe payments.
- Added support for push notifications and created a push notification extension. Integrated Swift Package Manager support.
- Built social media features with rich posts, comments, people, location tagging, sharing, and other feed actions. Provided smooth scroll performance, an intuitive UI, and efficient data load and persistence.
- Built an offline cache using Core Data and stored rich feed data.
- Tweaked misbehaving custom fonts. Used instruments to find performance bottlenecks. Built a custom scroll-based fading navigation bar.
- Extracted custom build settings to Xcode configuration files and schemes, making them easy to switch based on the environment—debug, QA, staging, and release.
- Displayed videos in the app using AVFoundation and applied image filters.
Technologies: Jira, Git, SnapKit, PromiseKit, Stripe, Core Data, Swift, iOS, Mobile Development, iOS Instruments, Object-oriented Programming (OOP), XCTest, Slack, UIKit, Unit Testing, Stripe Payments, AVFoundation, iOS Video, Social Media Apps, Figma, Mobile App Development, Mobile App Design, REST, APIs, Location Services and Maps, Location Services, Maps, Mobile, iOS SDK, iOS Native Libraries, Algorithms, iOS Frameworks, iOS API
iOS Development Consultant
2019 - 2019
WeSports
- Created a library for a lightweight Amazon Cognito sign-up process for Carthage.
- Created a test app to demonstrate usage of the library.
- Handled asynchronous tasks primarily using RxSwift.
Technologies: Amazon Cognito, Carthage, RxSwift, Swift, iOS, Mobile Development, SDKs, Object-oriented Programming (OOP), XCTest, Slack, Mobile, iOS SDK, iOS Native Libraries, iOS Frameworks, iOS API
Lead iOS Developer
2014 - 2019
SofaScore
- Contributed to the successful product SofaScore reaching 22 million MAUs and $10+ million in revenue.
- Split a legacy Objective-C codebase into several frameworks and integrated Swift support.
- Wrote hundreds of unit and snapshot tests, ensuring things didn't break. It sped up development, making team members more confident when releasing updates.
- Implemented a non-consumable in-app purchase and an auto-renewable subscription with local validation using OpenSSL.
- Created a library to facilitate table views with mixed table view cells and made seamless animated transitions between states.
- Implemented a watchOS app as well as Today and Intents app extensions.
- Refactored the core app using Promises to make data load and persistence seamless, fast, and efficient.
- Developed a multiplayer penalty shoot-out game from scratch using Swift and reusing existing underlying frameworks.
Technologies: BuddyBuild, Sirikit, StoreKit, SnapKit, PromiseKit, Git, CocoaPods, Objective-C, Swift, WatchOS, iOS, Mobile Development, Firebase, iOS Instruments, SwiftLint, Test-driven Development (TDD), SQLite, Object-oriented Programming (OOP), XCTest, Slack, Promise, Multithreading, Alamofire, YouTrack, Continuous Integration (CI), UIKit, Unit Testing, iPad, Mobile App Development, Mobile App Design, REST, APIs, CI/CD Pipelines, Real-time Data, Mobile, Algorithms, iOS SDK, iOS Native Libraries, iOS Frameworks, iOS API, Apple Watch
Software Engineering Intern
2015 - 2015
- Created a pixel-perfect UI and animations to enhance user engagement.
- Wrote code in Objective-C++ and fetched necessary data from a database using GraphQL.
- Deployed code to a codebase shared with hundreds of developers and shipped a component shown to new users on top of the news feed in the Facebook app.
- Improved accessibility for visually impaired persons.
- Wrote unit, snapshot, and end-to-end tests to cover every line of the code.
Technologies: GraphQL, ComponentKit, Mercurial, Objective-C++, Mobile Development, iOS Instruments, Object-oriented Programming (OOP), XCTest, Slack, Social Media Apps, Algorithms, Mobile
Software Developer
2013 - 2014
aiKATE
- Developed an application for tracking students' progress in the early stages of education and for direct communication between parents and teachers.
- Worked actively on processing input data and creating backup Excel files.
- Developed forms using ASP.NET to collect user input.
Technologies: Microsoft SQL Server, ASP.NET, C#, Object-oriented Programming (OOP)
Experience
ECF Lab
https://github.com/dstank25/ECF_LabECF Lab is a platform-independent desktop app written in Java developed to simplify usage of the Evolutionary Computation Framework written in C++. It manages parallel runs of experiments through interprocess communication independent of the background problem and algorithm.
Before ECF Lab, the user had to manually write configuration files and run experiments from the console, which was slow and error-prone. Results were in the form of plain text with no graphical representation. Professors and students would usually leave the app running overnight, and results were waiting for them in the morning saving them days and days of work.
Before ECF Lab, the user had to manually write configuration files and run experiments from the console, which was slow and error-prone. Results were in the form of plain text with no graphical representation. Professors and students would usually leave the app running overnight, and results were waiting for them in the morning saving them days and days of work.
Education
2014 - 2016
Master's Degree in Computer Science
Faculty of Electrical Engineering and Computing - Zagreb, Croatia
2011 - 2014
Bachelor's Degree in Computer Science
Faculty of Electrical Engineering and Computing - Zagreb, Croatia
Skills
Libraries/APIs
iOS Native Libraries, CocoaPods, SnapKit, PromiseKit, RxSwift, Alamofire, Stripe, Protobuf, iOS API
Tools
Xcode, Git, BuddyBuild, Slack, SwiftLint, iOS Instruments, Jira, Figma, Firebase Authentication, Amazon Cognito, Mercurial, Sirikit, YouTrack, IntelliJ IDEA, Confluence, CircleCI, Sentry, Fastlane, Braze, LaunchDarkly
Languages
Swift, Objective-C, C#, GraphQL, Java, Bash Script, Dart, Swift 5
Frameworks
iOS SDK, XCTest, SwiftUI, ASP.NET, StoreKit, ComponentKit, Viper, Core Data, UIKit, React Native, iOS Frameworks, Flutter
Paradigms
Mobile Development, Mobile App Design, Object-oriented Programming (OOP), Promise, Unit Testing, VIPER Architecture, REST, Model View ViewModel (MVVM), Continuous Integration (CI), Test-driven Development (TDD), Clean Architecture
Platforms
iOS, Mobile, WatchOS, Firebase, Apple Watch, FlutterFlow
Storage
Microsoft SQL Server, SQLite
Other
Mobile App Development, APIs, CI/CD Pipelines, Algorithms, Objective-C++, Multithreading, Carthage, SDKs, Amplitude, Segment, Airtable, Evolutionary Computation, Stripe Payments, React Native Bridge, Speech Recognition, AVFoundation, iOS Video, Social Media Apps, iPad, Architecture, Location Services and Maps, Location Services, Maps, Real-time Data
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