Peter is available for hire
Hire PeterPeter Zoller
Verified Expert in Engineering
Concurrency Developer
Budapest, Hungary
Toptal member since October 28, 2021
Bio
Peter is a professional mobile engineer with several years of experience in native app development. He's worked on many iOS and Android projects and has solved complex business problems in various industries, including fintech, transportation, human resources, energy, accounting, and pharmaceutical. Peter is passionate about creating high-quality software and building products that help companies grow.
Portfolio
FLIT Invest LLC
Swift, SwiftUI, Combine, Special Purpose Machines (SPM), Mixpanel...
Fincent Inc
Swift, iOS, Swift 5, SwiftUI, Fintech, Combine, UIKit, Mixpanel...
Freelance
Agile Software Development, iOS, Android, UIKit, Git, Swift, XCTest, Kotlin...
Experience
- iOS - 6 years
- Swift - 6 years
- UIKit - 6 years
- Objective-C - 3 years
- SwiftUI - 3 years
- Combine - 3 years
- XCTest - 3 years
- Concurrency - 1 year
Availability
Part-time
Preferred Environment
Xcode, Slack, Microsoft Teams, Agile Software Development, ClickUp, iOS, Swift, UIKit, SwiftUI, Combine
The most amazing...
...product I've developed is an invoicing application that takes the accounting experience for thousands of companies to a whole new level.
Work Experience
Lead iOS Developer
2022 - 2023
FLIT Invest LLC
- Created an iOS app that provides users with automated financial advice and investment management, focusing on generating positive, measurable social and environmental impact alongside a financial return.
- Worked closely with the product, UI/UX, and back-end teams to design, build, and extend existing and new features.
- Analyzed the technical feasibility of product features and helped to guide feature development and roadmap from a technical perspective.
- Led and mentored mobile engineers through design, code reviews, and engineering best practices.
- Built a custom UI component library that helped cut down the development time of the new features to half.
- Maintained a high level of code craftsmanship through thoughtful code reviews.
- Designed a testable, highly maintainable app architecture.
- Ensured the quality of the application via automated tests.
- Monitored the performance of the live app and continuously improved it on both code and UX levels.
Technologies: Swift, SwiftUI, Combine, Special Purpose Machines (SPM), Mixpanel, Mixpanel iOS SDK, AppsFlyer, iOS, Facebook SDK, Firebase, UIKit, Plaid, AWS Amplify, OneSignal, XCTest, XCUITest, SwiftyMocky, Framework Design, Clean Architecture, Charles Proxy, Figma, UI Animation, SwiftLint, SwiftGen, Concurrency, Stripe Payments, Stripe API, Amazon Web Services (AWS), API Integration, REST, Mobile Development, APIs, Architecture, Mobile, Algorithms
Senior iOS Developer
2021 - 2023
Fincent Inc
- Developed an iOS application that provides online bookkeeping services for numerous small businesses around the US.
- Led and mentored mobile engineers through design, code reviews, and engineering best practices.
- Laid the foundation of the app by designing a scalable, testable architecture.
- Implemented new features using bleeding-edge Apple frameworks like SwiftUI and Combine.
- Ensured the client's tech stack stayed current by adopting the latest language and framework advances.
Technologies: Swift, iOS, Swift 5, SwiftUI, Fintech, Combine, UIKit, Mixpanel, Mixpanel iOS SDK, Firebase, Firebase iOS SDK, Special Purpose Machines (SPM), Dependency Injection, Model View ViewModel (MVVM), Clean Architecture, Plaid, Charles Proxy, Figma, Stripe, SwiftGen, Concurrency, Stripe Payments, Stripe API, API Integration, REST, Mobile Development, APIs, Architecture, Mobile, Algorithms
iOS and Android Developer
2019 - 2021
Freelance
- Developed a customer service application for Hungary's leading energy supplier company. Transformed the old Objective-C codebase into a Swift-based application with brand new UI design.
- Built an integrated invoicing solution's iOS client for a leading Hungarian bank. Refactored the legacy application using the latest technologies, which resulted in a testable, maintainable codebase and improved app performance.
- Created an internal digital maintenance reporting Android application for a pharmaceutical company. This app helped push forward the company's digital transformation.
- Implemented a custom iOS UI library that could be used by the client's newly-created applications. This helped them to cut the costs of the upcoming projects significantly.
- Designed and implemented modular, testable, maintainable software architectures for several projects to reduce technical debt.
Technologies: Agile Software Development, iOS, Android, UIKit, Git, Swift, XCTest, Kotlin, CocoaPods, Android Studio, Jira, Special Purpose Machines (SPM), SwiftUI, Combine, Xcode, iOS SDK, iOS Native Libraries, VIPER Architecture, Clean Architecture, Model View ViewModel (MVVM), API Integration, REST, iPad, Mobile Development, Google Maps API, Location Services and Maps, Architecture, CI/CD Pipelines, Real-time Data, Mobile, Android SDK, Algorithms, Android API
iOS Developer
2018 - 2019
AutSoft Ltd.
- Developed and maintained numerous iOS applications.
- Rewrote multiple iOS apps from scratch using the latest technologies.
- Gained deep knowledge about Objective-C and Swift interoperability.
- Ensured the code quality with automated unit, integration, and UI tests.
- Did code reviews and helped other developers daily.
Technologies: iOS, Swift, Objective-C, CocoaPods, UIKit, XCTest, Fastlane, Agile Software Development, Git, Jira, iOS SDK, iOS Native Libraries, VIPER Architecture, API Integration, REST, iPad, Mobile Development, Architecture, Location Services and Maps, CI/CD Pipelines, Real-time Data, Mobile, Algorithms
Experience
FLIT Invest: Impact Investing
https://apps.apple.com/us/app/flit-invest-impact-investing/id1603265493FLIT Invest is an impact investing robo-advisor iOS app that provides users with automated financial advice and investment management, focusing on generating positive, measurable social and environmental impact alongside a financial return.
I led the app's development in a cross-functional Agile environment from day zero. I participated in the product development lifecycle, from initial ideas to publishing the app to the App Store and supporting it.
I led the app's development in a cross-functional Agile environment from day zero. I participated in the product development lifecycle, from initial ideas to publishing the app to the App Store and supporting it.
Fincent | iOS
Fincent is an iOS app for US-based SMBs to help manage their bookkeeping and finances.
I created the app's foundation using SwiftUI and Combine, but it also leverages UIKit for optimal rendering of large datasets on older iOS versions. Besides developing new features, fully custom UI components, and animations, I also had the chance to mentor and help my team members learn and utilize the latest technologies and engineering best practices.
I created the app's foundation using SwiftUI and Combine, but it also leverages UIKit for optimal rendering of large datasets on older iOS versions. Besides developing new features, fully custom UI components, and animations, I also had the chance to mentor and help my team members learn and utilize the latest technologies and engineering best practices.
E.ON Customer Service Application | iOS
I built a customer-service application for the leading energy-supplier company in Hungary. The app was created in Swift using the latest technologies, paying close attention to pixel-perfect UI design implementation.
The application provides many features, including submitting meter readings, paying bills, and managing personal and contractual information.
The application provides many features, including submitting meter readings, paying bills, and managing personal and contractual information.
E.ON Customer Service Application | Android
E.ON is the leading energy supplier company in Hungary. I maintained and developed new features for their customer service application.
Education
2019 - 2021
Master's Degree in Computer Science
Budapest University of Technology and Economics - Budapest, Hungary
2015 - 2019
Bachelor's Degree in Computer Science
Budapest University of Technology and Economics - Budapest, Hungary
Skills
Libraries/APIs
iOS Native Libraries, CocoaPods, Stripe API, Google Maps API, Android API, Mixpanel iOS SDK, Firebase iOS SDK, Stripe, Facebook SDK, AWS Amplify
Tools
Xcode, Charles Proxy, SwiftGen, Android Studio, Git, Fastlane, SwiftLint, Jira, Plaid, Figma, OneSignal
Languages
Swift, Swift 5, Objective-C, Kotlin
Frameworks
UIKit, SwiftUI, Combine, iOS SDK, XCTest, Android SDK, XCUITest, SwiftyMocky
Paradigms
Model View ViewModel (MVVM), VIPER Architecture, Mobile Development, REST, Agile Software Development, Dependency Injection, Clean Architecture
Platforms
iOS, Mobile, Android, Mixpanel, Firebase, AppsFlyer, Amazon Web Services (AWS)
Other
UI Animation, Concurrency, API Integration, iPad, APIs, Special Purpose Machines (SPM), Framework Design, Code Generators, Stripe Payments, CI/CD Pipelines, Real-time Data, Algorithms, ClickUp, Fintech, Location Services and Maps, Architecture
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