Jacek Szyja
Verified Expert in Engineering
Software Developer
Jacek is an experienced software engineer. During his career, he's had a chance to create projects for small startups and big global corporations. He gained experience in all project phases, from early project discussions and estimations through app development to releasing and analyzing results. Besides app development, Jacek is interested in mobile security.
Portfolio
Experience
Availability
Preferred Environment
Git, Xcode, MacOS
The most amazing...
...app I've made was for a fast food chain in UK. The sight of random people using it during my visit to London made me feel proud.
Work Experience
iOS Engineer
Self-employed
- Worked with a leading investment bank to help them expand into daily banking.
- Implemented SAML authentication, allowing US students to borrow ebooks on their phones.
- Created a social network experience for people working on their mindfulness.
- Helped people track their personal development progress thanks to beautiful charts.
iOS Developer
Goldman Sachs
- Charged with developing new features and fixing bugs that impact the end user experience the most.
- Implemented Marcus' fast track flow, making automatic saving more straightforward and engaging for users.
- Tasked with adding joint account-related features like showing transaction owner, assigning one if there isn't any, filtering, etc.
- Uplifted UI on transactions list and transaction details screens.
- Added many unit and snapshot tests throughout the app.
iOS Developer
HYD
- Developed mobile applications for well-established companies and global corporations in industries like food, transportation, photography, bio pharmacy, and more.
- Performed research projects for an augmented reality app and developed the back end in Swift with the Vapor framework.
- Developed complex custom UI components and animations.
- Provided consultation regarding the mobile app and system security.
- Configured analytics and made usage reports based on gained data.
iOS Developer
Softnauts
- Developed internal mobile applications and games for iOS.
- Developed mobile applications for startups and well-established companies.
- Worked remotely with clients in different time zones.
- Estimated the time needed to develop new projects and planned the development schedule.
iOS Developer
MeduTools
- Developed internal mobile application projects targeted at medical students.
- Redesigned and rewrote the flagship app from scratch.
- Optimized performance in downloading, manipulating, and saving data concurrently.
Experience
Marcus by Goldman Sachs
https://apps.apple.com/us/app/marcus-by-goldman-sachs/id1489511701I was part of a team responsible for adding new features and fixing bugs. I implemented automatic savings flow, allowing users to save monthly excess cash, features related to joint accounts, UI uplifting of transactions list and transaction details screens, and many smaller features.
iOS App for Greggs Fast Food Chain
https://www.greggs.co.uk/appLibrary Simplified
https://librarysimplified.orgI was responsible for implementing a SAML authentication into the app. This type of authentication is quite popular among universities but isn't widely used in mobile applications. Adding SAML opened the app for many new libraries. Other than that, I refactored some of the OAuth logic, added a new OAuth grant type, and refactored a class responsible for keychain data storage.
iOS App for Canon Europe
https://www.canon.pl/apps/photo-companion/The app featured content downloaded from the CMS with many different custom presentation types such as exercises, interactive maps, lens comparisons, and more.
I was a part of a two-person team. Communication between the client and the back end was secured with OAuth authentication.
iOS App for Stagecoach UK
Meditation App
https://www.flowly.worldI was responsible for creating:
• Community section
• Data analysis section
• Notifications section
• Rewards sections
Besides that, I also implemented a new home screen, refactored AV playback throughout the app, and unity integration in the project.
Audio Transmission App
Flooring App
iOS App for a Global Biopharmaceutical Company
I was the lead iOS developer in this project. It was written in Swift with the usage of the RxSwift ReactiveX library.
What's more, I also developed a back end for this project. I did it in Swift with the usage of the Vapor 2 framework and deployed it on AWS. Communication between the client and back end was secured with Oauth authentication.
iOS App for Arris
iOS App for Gift Card Granny
I was the lead developer responsible for app development. It originally was written in Objective-C, and later on, new features were added in Swift. Communication between the client and back end was secured with Oauth authentication.
iOS App for Portafill
I was the only developer on the project and made this app from scratch. It was written in Objective-C. Communication between the client and the back end was secured with OAuth authentication.
eTabu
https://etabu.xyz/en/Skills
Languages
Swift, Objective-C, GraphQL, SAML, C++, C, Java
Frameworks
Core Location, UIKit, MapKit, iOS SDK, SwiftUI, Core Data, AudioUnit, Viper, Spring, OAuth 2, JPA, Hibernate, Spring Boot, Boost, Redux, Vapor, ARKit, iOS SceneKit
Libraries/APIs
RxSwift, Alamofire, REST APIs, Fabric, Lottie-iOS, iOS Charts, CocoaPods, iOS API, iOS Native Libraries, ReactiveX, Firebase iOS SDK, AVKit, Sockets
Tools
Xcode, Slack, Git, Apple Push Notifications, GitHub, Bitbucket, Charles Proxy, Braintree SDK, AWS AppSync, Unity SDK, Postman, Jira, Figma
Paradigms
Agile Software Development, Concurrent Programming, Reactive Programming, Design Patterns, Model View ViewModel (MVVM), REST, Model View Controller (MVC), Continuous Delivery (CD), Continuous Integration (CI), Mobile Development, Scrum, Testing, VIPER Architecture, Agile, Unit Testing
Platforms
iOS, MacOS, Bitrise, Keychain, Firebase, Mobile, Docker, Amazon Web Services (AWS), AppsFlyer, AWS Elastic Beanstalk
Storage
JSON, PostgreSQL, SQLite
Other
GitFlow, Hockey, Flow Coordinators, Carthage, Lottie, WebKit, BrainTree, Objective-C++, GCD, Algorithms, APIs, Maps, SAML-auth, UDP, Payment APIs, CI/CD Pipelines, Reverse Engineering, Streaming
Education
Master of Science Degree in Computer Science
University of Science and Technology - Cracow, Poland
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