Stefan Progovac
Verified Expert in Engineering
Software Architecture Developer
Stefan is a highly skilled iOS developer with a master's degree in physics. He loves both the technological and artistic sides of software engineering. He's had the pleasure of working on some popular enterprise-level apps used by millions of people for companies like Target, Best Buy, and Roomi. Stefan believes that app development is truly an art.
Portfolio
Experience
Availability
Preferred Environment
Objective-C, Swift
The most amazing...
...app I've developed was Cartwheel for Target, an app that has touched so many people.
Work Experience
iOS Developer
Nina Chen
- Built a fashion app from scratch using SwiftUI and leveraging Stripe SDK for payments. All UI components and API layers were custom-built.
- Managed TestFlight and App Store releases. Consulted in best practices and guided the app to the final stages of development.
- Allowed for capturing photos, drag and drop of custom text and images, resizing of photos, and more.
iOS Tech Lead
Scooter's Coffee
- Developed a new version of Scooter's app in SwiftUI from scratch, managing a team of two iOS developers. Oversaw all architectural decisions, set up the CI/CD pipeline using CI/CD pipeline for GitHub, and oversaw provisioning and releases.
- Tracked and fixed stories in Jira, documented procedures in Confluence, used Sketch and Abstract for app designs, and managed image assets.
- Oversaw the design, requirements phase, and building of a new app written in SwiftUI for Scooter's Coffee. Overcame challenges like keeping users logged in from their previous app and interfacing with LevelUp.
Senior Developer
Dexcom
- Wrote a prototype of the G7 App for Dexcom in Flutter, which was used as part of the Food and Drug Administration (FDA) approval process while the flagship app was developing.
- Tracked and fixed issues in Trello and GitHub and used Figma for designs.
- Oversaw the launch and deployment of the prototype in formatives to help train users and regulators, which was an integral part of the FDA approval process.
Senior iOS and Swift Developer
Swift Medical
- Worked actively on a cutting-edge and innovative healthcare app with a device called Sinatra, connected to the phone via Bluetooth Low Energy (BLE), which takes and analyzes photos of wounds and aids doctors and nurses in tracking progression.
- Contributed to all aspects of the app and created a standalone app that helped the team provision Sinatra devices.
- Completed new features of the app, such as working on bacterial analysis, single-form evaluation, and other thermal imaging analyses for the app.
Senior iOS Developer
Catapults Sports LLC
- Worked on instrumental in the live streaming of this sports app, syncing multiple angles to stream effortlessly as the user went from angle to angle.
- Managed the entire CI/CD pipeline, Apple Store account, and release process as a sole developer.
- Fixed numerous issues, usually around video editing, and implemented a caching layer to make streaming more efficient for very long videos and potentially slow internet connections.
Senior iOS Developer
Anthem, Inc.
- Helped design the navigation bridge between the iOS-embedded navigation stack and the React Native navigation scheme.
- Worked on device integration; the app tracked steps, sleep, and weight through syncing with HealthKit and more.
- Built accessibility to comply with all federal regulations.
- Provided unit testing and automated builds with Jenkins pipelines.
- Developed push notifications with embedded rich content inside the messages.
Senior iOS Developer
AutoLoop, LLC
- Leveraged gelocation for marketing purposes.
- Wrote an entire UI and unit test suite.
- Wrote scripts in Fastlane to fully automate the release—perform screenshots, run all tests, and make releases.
- Built custom UI and animation.
- Wrote an app to facilitate the check-in procedure for car dealers.
iOS Developer
Latch
- Helped with the reskinning of the UI for the release.
- Worked on debugging issues with Bluetooth connection using BLE protocol.
- Created custom UI components, like piecharts using Core Graphics.
Senior iOS Developer
Max2, Inc.
- Worked on a payment module that required Bluetooth interfacing with hardware.
- Formatted ISO 8583 messages intended to securely process payments.
- Developed a chat module leveraging web sockets.
- Worked with remote and in-app notifications.
- Worked with Twitter, FB, and Instagram SDKs. The app promotes social media interactivity.
- Built a custom UI.
- Wrote an app that allows users to search for, view, and rate venues as well as purchase items and do transactions.
iOS Developer
Stand Technologies
- Oversaw this project for a small stand-up company from development to release on the App Store.
- Implemented push notifications, including writing server-side code.
- Created a custom networking layer, including efficient categories for image caching and setting UIImageViews, with the ability to cancel or reuse requests if the UIImageView would happen to be reused (such as in a reusable cell) using associated objects.
- Used Facebook APIs for login.
- Created a custom newsfeed using dynamic row heights for added flexibility.
Senior iOS Developer
Roomi
- Integrated Parse and Layer to build native chat into the app.
- Worked with Core Animation, Core Text, and CALayer to customize the user experience.
- Used advanced techniques, such as object swizzling, to override default behavior and enhance functionality.
- Worked with Parse's cloud and developed and maintained scripts in JavaScript.
- Worked extensively with push notifications.
iOS Developer
Best Buy
- Redesigned and rewrote the entire Best Buy app in Swift.
- Architected the app based on the VIPER paradigm.
- Made use of new Apple technologies such as app extensions and their widgets, primarily for advertisements.
- Experimented with iBeacons. Best Buy was one of the first stores to embed iBeacons into their department store lighting.
- Began working on Apple Pay for a more seamless checkout experience using the Best Buy app.
- Replaced the zBar scanner with a native Apple scanner for barcodes.
- Implemented fast image caching across the application.
Senior iOS Developer
ConXus Lochinvar
- Redesigned the UI to look appropriate for the iPhone. Previous developers had only paid attention to the iPad.
- Gained extensive experience with auto layouts of all forms.
- Worked with the Microsoft Cloud and Azure.
iOS Developer
Target (Cartwheel)
- Worked on implementing a highly automated environment. Employed a dedicated Jenkins server and Xcode bots and hooks so every Git checkin for the QA would get the latest build to Test Flight.
- Worked with Crashlytics for bug tracking.
- Worked with true Agile methodologies and Jira for efficient work progress.
- Worked extensively with PassKit and CocoaPods.
- Made extensive use of OAuth tokens to guard sessions for items added to cart, as well saved payment information (each having their own tokens).
- Used Google Postman to debug and document RESTful APIs.
iOS Developer
Rockwell Collins
- Made extensive use of MapKit and Waypoints for plotting airplane itineraries.
- Made a custom calendar from UICollection View.
- Made extensive use of core data as a kind of cache for data, including using helpful third-party tools like Mogenerator.
- Implemented extensive security features, such as storing in the keychain and various hashing and encryption algorithms.
- Used regular expressions for input validation to prevent SQL injections.
Experience
Cartwheel App
Best Buy
https://itunes.apple.com/us/app/best-buy/id314855255?mt=8SmartLane
https://itunes.apple.com/us/app/smartlane/id686173091?mt=8Ascend Flight Manager
Roomi
https://roomiapp.comSTAND
Senior Software Developer for Max2
LATCH
https://apps.apple.com/us/app/latch-app/id1062355375Skills
Languages
Swift, XML, Objective-C, JavaScript, Kotlin, Java, Python, C++, C#, GraphQL
Frameworks
OAuth 2, AFNetworking, Core Data, SwiftUI, Flutter, React Native
Libraries/APIs
CocoaPods, Parse SDK, Layer API, Apple Maps API, Kiwi, Mantle, Google API, Facebook SDK, jQuery, Core Animation, Stripe API
Tools
Hockey SDK, Crashlytics, GitHub, Git, Jira, Xcode, Slack, Apple Push Notifications, Suds, Pivotal Tracker, Asana
Paradigms
Agile Software Development, Mobile Development, Unit Testing
Platforms
Bluetooth LE, iOS, Apple Watch, Firebase, Parse
Storage
JSON
Other
OAuth, Geolocation, Programming, Freelancing, IT, AVFoundation, Software Architecture, Machine Learning, Augmented Reality (AR), Carthage, Bluetooth, AVCaptureSession, Leadership, Video Capture, User Experience (UX), CI/CD Pipelines, Mobile App Development, Apple Pay, Apollo
Education
Master of Science Degree in Physics
University of California San Diego - San Diego, USA
Bachelor of Science Degree in Mathematics
Michigan State University - East Lansing, USA
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