Vladimir is available for hire

Vladimir Kaltyrin

Verified Expert in Engineering

Mobile Architect and iOS Developer

Location

Tel Aviv-Yafo, Israel

Toptal Member Since

July 29, 2020

Vladimir has gained solid enterprise experience in top tech companies. In addition, he has worked for a European startup, and a leading outsource mobile agency. Vladimir has worked with a large team of 50 iOS developers to develop an app for Avito, considered the second most popular classified platform globally by the SimilarWeb ranking. He is experienced with iOS, Swift, Git, Agile, Scrum, and Atlassian products and is good at cross-functional team communication.

iPad GitFlow iOS Guides Push Notifications Mobile App Development Mobile Applications Accessibility UI Testing Code Review iOS Xcode iOS SDK iOS Native Libraries Objective-C Git

Portfolio

Popular Pays Inc

Swift, APIs, Agile Software Development, SwiftUI, UIKit...

Pensend

iOS, Swift, SwiftUI, Mathematics, APIs, UI Frameworks, iOS Native Libraries...

Stanley Park

iOS, Swift, Firebase, Google Cloud, AVFoundation, iOS Native Libraries, iOS SDK...

Experience

Xcode - 10 years iOS - 10 years Git - 8 years REST APIs - 8 years Mobile Architecture - 7 years Swift - 7 years Agile Software Development - 5 years SwiftUI - 4 years

Availability

Part-time

Preferred Environment

GitHub, Zeplin, App Development, Figma, Trello, Jira, Bitbucket, Slack, Xcode, MacOS

The most amazing...

...features I've developed were for the Avito mobile app, which has more than 25 million monthly active users.

Work Experience

Senior iOS Developer

2022 - 2023

Popular Pays Inc

Developed and maintained the mobile application reaching a crash-free rate of 99%.
Leased with managers and released multiple features for creators and brands.
Set up mobile development processes within the team, launched the release train, and achieved a regular release every two weeks.
Built new features and improved the time-to-market metric using SwiftUI.

Technologies: Swift, APIs, Agile Software Development, SwiftUI, UIKit, Model View Viewmodel (MVVM)

Senior iOS Engineer

2022 - 2022

Pensend

Developed a highly customizable plot view similar to plots at Khan Academy and built it entirely in SwiftUI.
Implemented comprehensive animations, gestures, scale factors, and drawings of any equation.
Built a demo project that utilized the API and consulted the client on the library integration into the app.

Technologies: iOS, Swift, SwiftUI, Mathematics, APIs, UI Frameworks, iOS Native Libraries, iOS SDK, Mobile Development, Alamofire, iOS Frameworks

Senior iOS Developer

2021 - 2022

Stanley Park

Developed an app for surgeons that allows them to edit videos of operations and put annotations above the video.
Created a fully-functional video editor from scratch, enabling trimming, merging videos, adding audio overlays, and uploading the edited video to the server.
Built a custom UI for a video editor and utilized drag-and-drop, swipe, and scale gestures.
Improved the performance of producing the video timeline for large videos (10GB). After an improvement, the timeline started to display frames instantly without any delay.

Technologies: iOS, Swift, Firebase, Google Cloud, AVFoundation, iOS Native Libraries, iOS SDK, Accessibility, Mobile Architecture, Mobile Development, Video Codecs, Alamofire, iOS Frameworks, Video Editing, Image Manipulation

Senior iOS Developer

2020 - 2022

Toptal Clients

Developed an eCommerce app from scratch using Swift for iOS and JavaScript and Express.js for the back end.
Created a real-time messenger feature for an eCommerce app.
Built an architecture and design system for an eCommerce app. It included MVVM, dependency injection (DI) using Swinject, and the advanced usage of UIKit for the custom UI.
Implemented a push notification server and executed the handling of push notifications on the client.
Developed Firebase Dynamic Links both on iOS and the back end.
Provided consultancy services for a client's team on the best iOS practices and offered a code review.
Built an app for an enterprise IoT and security company in the US that heavily utilized the Core Location framework to track the user's location in the background, even if the app is terminated.
Improved the battery performance by 30% in the app for an enterprise IoT and security company in the US.
Led the development of an MVP iOS app as a mobile architect and built a mobile app in SwiftUI and a back end. The app allowed a construction worker to film 360 videos, put them on an interactive floor plan of a building, and upload them to the cloud.

Technologies: Swift, Firebase, Node.js, Express.js, GitHub, Messenger, SwiftUI, UIKit, Startups, APIs, Core, Minimum Viable Product (MVP), Back-end, Freelancing, Mobile App Development, Mobile Applications, Software Architecture, Encryption, Full-stack, Amazon Web Services (AWS), iOS Native Libraries, iOS SDK, Internet of Things (IoT), Bluetooth, Accessibility, Location Services, Mobile Architecture, Technical Leadership, Bluetooth LE, Video Streaming, Core Motion, Design, Mobile Development, Android, Video Codecs, Realm, Alamofire, iOS Frameworks, Google Maps SDK, Lottie-iOS, Lottie, Flutter, Image Manipulation

iOS Tech Lead

2018 - 2020

Sberbank

Developed a popular real estate app widely used to buy and rent a flat and obtain a mortgage. The app is associated with the top bank in Eastern Europe.
Built a new enterprise iOS app for an iPad from scratch. Account managers in all bank offices use this app, significantly reducing the paperwork for both managers and clients.
Developed an enterprise iOS Instagram-like app from scratch, which heavily uses the camera and core data.
Created a Swift front end for a 3D-panorama similar to Google Street View written in C++ and integrated it with the native camera. It required the advanced use of the AVFoundation framework, OpenGL rendering, and developing the REST API client's side.
Developed cross-platform business logic, using Kotlin Multiplatform for several features.
Improved development tools and CI/CD constantly, using Fastlane, introduced SwiftLint, and accelerated the build time of the Domclick app by ten times, from 15 minutes down to 1.5 minutes.
Organized unit and UI testing workshops and promoted testing practices.
Integrated a Firebase Remote Config, Firebase A/B tests, analytics, and Cloud Firestorage into an iOS app.
Provided consultancy on writing clean code in Swift. Participated in daily code reviews. Liaised with product managers, designers, and back-end developers. Promoted Agile principles and organized scrum retrospectives.
Managed the App Store submission and approval process.

Technologies: Videos, API Architecture, Swift 4, Continuous Delivery (CD), Mobile, Push Notifications, Authentication, Authorization, Deep Linking, UIKit, Core Animation, React, Git, Xcode, UI Testing, iOS Guides, iPad, Viper, Firebase, RxSwift, JavaScript, Python, Kotlin, Core Data, CocoaPods, Swift, iOS, Native Mobile Apps, Cross-platform, Mobile Apps, Apple, User Interface (UI), User Experience (UX), Animation, StoreKit, SwiftUI, Code Review, Source Code Review, Task Analysis, Technical Hiring, Interviewing, Architecture, CTO, Minimum Viable Product (MVP), Project Management, Mobile App Development, Mobile Applications, Software Architecture, PostgreSQL, Encryption, Amazon Web Services (AWS), iOS Native Libraries, iOS SDK, Accessibility, Location Services, Mobile Architecture, Technical Leadership, Mobile Development, Alamofire, iOS Frameworks, Flutter

iOS Developer

2016 - 2018

Avito

Developed and launched major features for the most popular classified iOS app in Eastern Europe, the Avito app, with more than 1 million daily active users (DAU).
Built seller and buyer profiles, ratings and reviews, authorization, and registration.
Developed a cropping module for an open-sourced custom iOS camera framework Paparazzo.
Designed and developed core application components and implemented complex and efficient UI elements, including a library of UI components and a networking library.
Improved code quality by implementing UI and unit tests providing code coverage up to 90% in corresponding product squad modules.
Participated in features grooming and worked closely with product and back-end teams in the fast-paced environment following the Scrum methodology.
Provided consultancy on clean code, SOLID, and VIPER architecture daily by participating in code review and meetings.

Technologies: Videos, API Architecture, Swift 4, Continuous Delivery (CD), Mobile, Push Notifications, Authentication, Authorization, Deep Linking, UIKit, Core Animation, Git, Xcode, UI Testing, iOS Guides, iPad, Viper, Amplitude, TeamCity, Scrum, Objective-C, CocoaPods, Swift, iOS, Native Mobile Apps, Mobile Apps, Swift 3, Apple, User Interface (UI), User Experience (UX), Animation, StoreKit, Code Review, Source Code Review, Mobile App Development, Mobile Applications, Software Architecture, PostgreSQL, Encryption, Amazon Web Services (AWS), iOS Native Libraries, iOS SDK, Accessibility, Mobile Architecture, Technical Leadership, Mobile Development, Alamofire, iOS Frameworks, Image Manipulation

Senior iOS Developer

2014 - 2016

StrongLifts LLC

Developed a StrongLifts 5x5 iOS app from scratch in Objective-C, and the app was recognized as a top-quality fitness app in the US by the Applause study in 2016.
Built a cloud back end using the Parse Server and data synchronization framework between client and cloud server.
Developed a graphs module. It allows users to visualize workout data on a graph.
Researched a prototype of the Apple Watch app for a workout app.
Managed the App Store submission and approval process.

Technologies: Mobile, Push Notifications, Authentication, Authorization, UIKit, Core Animation, CocoaPods, Git, iOS, Xcode, iOS Guides, iPad, Viper, Apple Watch, Zeplin, Travis CI, GitHub, Swift, SQLite, Parse, Core Data, Objective-C, Native Mobile Apps, Mobile Apps, Swift 3, Apple, User Interface (UI), User Experience (UX), Animation, Apple HealthKit, StoreKit, WatchOS, Mobile App Development, Mobile Applications, Software Architecture, Encryption, iOS Native Libraries, iOS SDK, Core Motion, Mobile Development, Alamofire, iOS Frameworks

iOS Game Developer

2014 - 2014

Fun Factory LLC

Launched an iPad version of a popular hidden object game.
Developed a library of UI elements and animation transitions for game development.
Developed and launched an entirely new level in the game.
Managed a continuous integration process in Jenkins.

Technologies: Mobile, Push Notifications, Authentication, Authorization, UIKit, Core Animation, Git, Xcode, iOS Guides, Subversion (SVN), Jenkins, Cocos2d, iPad, Objective-C, iOS, Native Mobile Apps, Mobile Apps, Apple, Animation, Mobile App Development, Mobile Applications, Software Architecture, Encryption, iOS Native Libraries, iOS SDK, Mobile Development, Alamofire

iOS Developer

2013 - 2014

Sebbia

Built a REST API for a client for a popular analytics SDK.
Created a shopping app that allows users to scan the barcode and find a grocery item using the REST API.
Developed an interactive quiz app for a psychologist.

Technologies: Mobile, Push Notifications, Authentication, Authorization, UIKit, Core Animation, CocoaPods, Git, Xcode, iOS Guides, iPad, Jenkins, Model View Controller (MVC), iOS, Objective-C, Native Mobile Apps, Mobile Apps, Apple, StoreKit, Mobile Applications, Software Architecture, Encryption, iOS Native Libraries, iOS SDK, Mobile Development, Ejabberd, iOS Frameworks

Experience

I developed and maintained the Popular Pays iOS application, reaching a crash-free rate of 99%. For that, I used SwiftUI to accelerate the time-to-market metric. I also launched multiple features, wrote UI tests, and leased with managers in the agile team.

StrongLifts

https://apps.apple.com/gb/app/stronglifts-5x5-weight-lifting/id488580022

A popular fitness tracker app. It displays the workout statistics, graphs, and it has data synchronization between different devices. One of the main features is a cloud backup supporting iCloud and Google Drive.

Avito

https://rb.gy/5x8sn

I was part of a strong team that developed an iOS application for Avito, the number one classified platform in CIS and number two classified worldwide after Craigslist.com. I started working in the platform squad, contributing to dozens of core components. Then I moved to a product squad where I developed features and implemented A/B tests. The app has about 1,000,000 DAU.

Domclick

https://rb.gy/fdoc0

It's a popular real estate app that is used to rent or buy a flat. Moreover, the app automates the way of getting the mortgage. I developed every part of the project from core components to architecture and main features. The app has a rich user interface including chat, map, and rich detailed views.

Pensend

https://apps.apple.com/gb/app/pensend/id1571322730

Pensend is an educational iOS app used to learn math by students. While working on this project, I built a highly customizable plot view similar to plots at Khan Academy and developed it entirely in SwiftUI.

Auto.ru

https://rb.gy/ccppm

A Swift-based iOS app for a popular car sales marketplace. I developed authorization and registration, restored passwords, several UI components, keychain storage, and part of the networking layer. Also, I refactored core modules to VIPER architecture.

Analytics SDK

I developed a REST client for an analytics SDK similar to Google Analytics. It was an MVP version of iOS SDK for the analytics platform for the European company. I was involved in the design of convenient software API and writing unit and E2E tests.

Goods

An app in Objective-C for searching for goods using a bar-code scanner. The app allowed users to find and rate the grocery item. I developed UI and HTTP requests for a barcode scanner, ratings, comments, and user authorization flow.

Get100

A well-designed classical puzzle game in Objective-C and UIKit. The goal of the game is to arrange arithmetic signs and parenthesis in such a way that the whole expression is equal to 100. I developed the app from scratch.

Quizanika

A quiz iOS app for a psychological training. I developed a SQLite database to persist list of questions and added a voice synthesiser framework by Apple to support the accessibility for the people with disabilities.

Paparazzo (open-source iOS camera)

https://github.com/avito-tech/Paparazzo

Open-source media picker in Swift language built on top of AVFoundation, AVCaptureSession, Core Image, and Core Video. I made a contribution to a core camera module as well as developed a crop feature.

Surgiyo (via Toptal)

https://www.surgiyo.com

Built an app for surgeons to manage and edit videos of surgeries. I developed this app from scratch using Swift and AVFoundation. The video editor is the core feature and it supports audio, video, and text overlays similar to Instagram Reels. Besides the video editor, it has a built-in real-time messenger.

Skills

Languages

Swift, Objective-C, Swift 4, Swift 5, Swift 3, Bash, Bash Script, SQL, JavaScript, Kotlin, TypeScript, Python 3, Dart, Python

Frameworks

iOS SDK, Core Data, UIKit, iPhone SDK, RealmSwift, Core Location, CODE, Viper, StoreKit, SwiftUI, Core Motion, iOS Frameworks, Flutter, Core Video, ReactiveCocoa, Cocos2d, Express.js

Libraries/APIs

CocoaPods, Alamofire, Core Image, Firebase iOS SDK, iOS API, Fabric, Core Animation, iOS Native Libraries, REST APIs, Twitter SDK, Facebook iOS SDK, RxSwift, RxSwift 4, Google Maps, Lottie-iOS, Telegram Messenger API, Parse SDK, React, Node.js, Google Maps SDK

Tools

Xcode, AppCode, Bitbucket, Git, Sublime Text 3, Fastlane, Slack, Skype, Zoom, Apple Push Notifications, Firebase Analytics, Asana, SwiftLint, Jira, Trello, Auto Layout, Apple HealthKit, Figma, Zeplin, GitLab CI/CD, Moya, Jenkins, IntelliJ IDEA, Android Studio, Travis CI, TeamCity, Sketch 2, Sketch 3, Sketch 4, GitHub, Subversion (SVN), Crashlytics

Paradigms

Unit Testing, Agile Software Development, VIPER Architecture, Model View Presenter (MVP), Model View Controller (MVC), Model View Viewmodel (MVVM), Object-oriented Programming (OOP), Mobile Development, RESTful Development, Continuous Delivery (CD), Continuous Integration (CI), Coded UI Tests, Scrum, Design Patterns, Dependency Injection, App Development, Cross-platform, Clean Architecture, Clean Code, Reactive Programming, API Architecture, Functional Programming, Web Architecture

Platforms

iOS, Apple Watch, Firebase, iOS 11, iOS 10+, Mobile, Apple, iOS 12, Parse, WatchOS, Bluetooth LE, Android, MacOS, Amazon Web Services (AWS)

Storage

SQLite, Realm, Google Cloud, PostgreSQL

Other

iOS Camera, AVFoundation, iPad, GitFlow, App Store, Mobile App Testing, iOS Design Guidelines, UI Testing, OOP Designs, iOS Guides, Computer Skills, MacBook, Team Leadership, Mobile Architecture, DI, App Store Acceptance Process, Mobile Apps, Startups, SOLID Principles, Networking, Accessibility, Deep Linking, Authorization, Authentication, Push Notifications, Native Mobile Apps, Code Review, Source Code Review, Task Analysis, Technical Hiring, Interviewing, Architecture, Minimum Viable Product (MVP), Mobile App Development, Mobile Applications, Location Services, Location Services and Maps, Technical Leadership, Video Streaming, Video Editing, Image Manipulation, Algorithms, A/B Testing, Hybrid Apps, Scrum Master, Mobile/Web Project Management, Code Architecture, OSI Model, BaaS, Amplitude, Videos, User Experience (UX), Spatial Reasoning, Animation, Freelancing, Software Architecture, Full-stack, Mathematics, UI Frameworks, Internet of Things (IoT), Bluetooth, Video Codecs, Lottie, Graph Theory, Machine Learning, Data Structures, Discrete Mathematics, Mobile GPS, Crypto, Messenger, User Interface (UI), iOS Animations, Messaging, APIs, Core, CTO, Back-end, Encryption, Design, Ejabberd, Voice Chat

Industry Expertise

Project Management

Education

2011 - 2013

Master's Degree in Computer Science and Applied Mathematics

Southern Federal University - Rostov-on-Don, Russia

2007 - 2011

Bachelor's Degree in Computer Science and Applied Mathematics

Southern Federal University - Rostov-on-Don, Russia

Certifications

FEBRUARY 2020 - PRESENT

Codility Golden Award for the Palladium 2020 Challenge

Codility