Jan Wisniewski, Developer in Rzeszow, Poland
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Jan Wisniewski

Verified Expert  in Engineering

Bio

Jan is a seasoned software engineer with 18 years of experience in the software industry. He has seven years of professional experience as a full-stack developer and 11 years in mobile development. Jan has a proven track record in leading development teams and delivering high-quality applications across various industries.

Portfolio

Asseco Data Systems
Swift, SwiftUI, Combine, React, React Native, JavaScript, TypeScript, iOS...
Bank Millennium
Swift, UIKit, User Interface (UI), User Experience (UX), iOS SDK, Architecture...
Comarch
Swift, Objective-C, UIKit, Java, Spring Boot, React, React Native, JavaScript...

Experience

  • Xcode - 16 years
  • iOS - 14 years
  • UIKit - 10 years
  • Swift - 6 years
  • React Native - 4 years
  • SwiftUI - 4 years
  • React - 4 years
  • Combine - 4 years

Availability

Full-time

Preferred Environment

MacOS, iOS, Xcode, Swift, React, TypeScript

The most amazing...

...app I've developed is Transport GZM. It combines all available providers into one system and allows commuters to travel without worrying about tickets.

Work Experience

Senior Software Engineer

2021 - PRESENT
Asseco Data Systems
  • Delivered two public transport telematics apps for metropolitan areas with a target user base of seven million users.
  • Developed full lifecycle, iOS front-end systems and provided platform expertise.
  • Helped with the design of the main features within the iOS app.
Technologies: Swift, SwiftUI, Combine, React, React Native, JavaScript, TypeScript, iOS, MacOS, Xcode, User Interface (UI), User Experience (UX), Prototyping, iOS SDK, Android, Architecture, Mobile Development, Decentralized Systems, Networking, Kotlin, Software Development, JSON, REST APIs, APIs, Apple Watch, Mobile Apps, Core Data, Core Bluetooth, Near-field Communication (NFC), Front-end, Agile Software Development, CI/CD Pipelines, Data Structures, Mobile App Development, Database Architecture, Cloud, Firebase, Online Payments, Consumer-facing Products, App Store, Bluetooth, OAuth, Mobile, Apps, Coding, Software, iOS Native Libraries, IoT Security, Bluetooth Low Energy (LE), App Store Acceptance Process, RESTFul APIs, API Integration, SMS, GraphQL, Security, Expo, Real-time Data, Real-time Systems, Figma, Microservices, Data Visualization, Model View ViewModel (MVVM), Async/Await, Asynchronous Programming, GitHub, Subscriptions, Growth, VPN, GitLab CI/CD, Redux

Team Lead and Senior Software Developer

2021 - 2021
Bank Millennium
  • Led a team to deliver the Junior app, a version of the bank's main user app.
  • Delivered a version of the app for young clients below the age of 13, with over 100,000 downloads in the first few weeks.
  • Provided technical leadership and expertise to junior team members.
Technologies: Swift, UIKit, User Interface (UI), User Experience (UX), iOS SDK, Architecture, Leadership, Mobile Development, Decentralized Systems, Networking, Software Development, JSON, REST APIs, APIs, Apple Watch, Mobile Apps, Core Data, Near-field Communication (NFC), Front-end, Agile Software Development, CI/CD Pipelines, Data Structures, Mobile App Development, Technical Leadership, Database Architecture, Cloud, Firebase, MacOS, Online Payments, Consumer-facing Products, App Store, OAuth, Mobile, Apps, Coding, Software, iOS Native Libraries, RESTFul APIs, API Integration, SMS, GraphQL, Security, Figma, Model View ViewModel (MVVM), Asynchronous Programming, GitHub, A/B Testing, Subscriptions, VPN, Exchanges

Lead Senior Developer

2019 - 2020
Comarch
  • Managed full mobile stack development of the Spring Boot and WildFly back end and the iOS front end.
  • Developed major raw data collection and analysis modules with a presentation of readable statistics.
  • Wrote services that provided data collected from devices for a comprehensive presentation in the user feed.
  • Supported and extended the functionality of apps for semiconductor producers using Bluetooth for connection and control.
Technologies: Swift, Objective-C, UIKit, Java, Spring Boot, React, React Native, JavaScript, TypeScript, Xcode, iOS, WildFly, Prototyping, User Interface (UI), User Experience (UX), iOS SDK, Android, Architecture, Leadership, Mobile Development, Decentralized Systems, Networking, Kotlin, Full-stack, Software Development, JSON, REST APIs, APIs, Amazon Web Services (AWS), Apple Watch, Mobile Apps, Core Data, Core Bluetooth, UI Design, Front-end, Agile Software Development, CI/CD Pipelines, Data Structures, Mobile App Development, Technical Leadership, Web Architecture, Database Architecture, Cloud Infrastructure, Cloud, MongoDB, Firebase, TestFlight, MacOS, Online Payments, RxSwift, Consumer-facing Products, In-app Purchase (IAP), App Store, WebSockets, AVFoundation, Bluetooth, Back-end, OAuth, Identity & Access Management (IAM), Mobile, Apps, Coding, Software, Embedded C++, C++, 3D CAD, iOS Native Libraries, Embedded Systems, IoT Security, Embedded C, Bluetooth Low Energy (LE), App Store Acceptance Process, RESTFul APIs, App Store Optimization (ASO), Full-stack Development, Software Architecture, Early-stage Startups, Messaging, Minimum Viable Product (MVP), API Integration, SMS, DevOps, Security, Node.js, NestJS, Real-time Data, Real-time Systems, Wearable Technology, Wearables, CSS, HTML, Figma, Streaming, Microservices, Docker, Kubernetes, Data Visualization, Model View ViewModel (MVVM), Asynchronous Programming, GitHub, Subscriptions, Growth, VPN, Heroku, Redux

Senior Engineer

2015 - 2018
Mobica
  • Developed apps for major telecommunication companies with multimillion daily usage.
  • Built apps in various industries, including semiconductors, media streaming, and aviation.
  • Mentored junior developers and conducted technical interviews.
  • Developed apps for the biggest semiconductor producers using Bluetooth for connection and control.
Technologies: Swift, Objective-C, UIKit, Java, Spring Boot, React, React Native, JavaScript, TypeScript, Prototyping, User Interface (UI), User Experience (UX), iOS SDK, Android, Architecture, Leadership, Mobile Development, Decentralized Systems, Networking, Kotlin, Full-stack, Software Development, JSON, REST APIs, Python, APIs, Amazon Web Services (AWS), Apple Watch, Mobile Apps, Core Data, Core Bluetooth, UI Design, Front-end, Agile Software Development, CI/CD Pipelines, Data Structures, Mobile App Development, Technical Leadership, Web Architecture, Database Architecture, Cloud Infrastructure, Cloud, MongoDB, Firebase, TestFlight, MacOS, Online Payments, RxSwift, Consumer-facing Products, In-app Purchase (IAP), App Store, WebSockets, AVFoundation, AppKit, Bluetooth, Back-end, OAuth, Identity & Access Management (IAM), PostgreSQL, Mobile, Apps, Coding, Software, Embedded C++, C++, 3D CAD, iOS Native Libraries, Embedded Systems, IoT Security, Embedded C, Bluetooth Low Energy (LE), App Store Acceptance Process, RESTFul APIs, App Store Optimization (ASO), Full-stack Development, Software Architecture, Early-stage Startups, Messaging, Minimum Viable Product (MVP), API Integration, SMS, DevOps, Security, Node.js, Real-time Data, Real-time Systems, Wearable Technology, Wearables, CSS, HTML, Social Networks, Streaming, Microservices, Docker, Kubernetes, Data Visualization, Model View ViewModel (MVVM), Asynchronous Programming, GitHub, A/B Testing, Subscriptions, Growth, VPN, MySQL, Heroku, Exchanges, WebRTC

Lead iOS Developer

2013 - 2014
Norbelle LLC
  • Developed and helped with the design of the main product's iOS app.
  • Managed the entire development lifecycle of the iOS app, from specification to App Store release.
  • Designed the architecture, published it on iTunesConnect, and provided technical expertise.
Technologies: Objective-C, UIKit, Prototyping, iOS SDK, Android, Architecture, Leadership, Mobile Development, Decentralized Systems, Networking, Full-stack, Software Development, REST APIs, APIs, Amazon Web Services (AWS), Mobile Apps, Core Data, Core Bluetooth, UI Design, Front-end, Agile Software Development, Data Structures, Mobile App Development, Technical Leadership, Database Architecture, Cloud, Online Payments, Consumer-facing Products, StoreKit, In-app Purchase (IAP), App Store, WebSockets, AVFoundation, AppKit, Bluetooth, Back-end, Identity & Access Management (IAM), Mobile, Apps, Coding, Software, iOS Native Libraries, IoT Security, App Store Acceptance Process, RESTFul APIs, App Store Optimization (ASO), Full-stack Development, Software Architecture, Early-stage Startups, Messaging, Minimum Viable Product (MVP), API Integration, DevOps, Security, Real-time Data, Real-time Systems, Wearable Technology, Wearables, Social Networks, Streaming, Microservices, Model View ViewModel (MVVM), Asynchronous Programming, GitHub, Growth, VPN, Heroku

Team Lead

2011 - 2013
Applico
  • Designed the architecture and developed mobile apps for various industries.
  • Provided technical leadership and expertise to designers, managers, and junior team members.
  • Leveraged multi-platform technologies, from a Java back end to an iOS and Android front end.
Technologies: iOS, UIKit, Objective-C, Java, Spring Boot, Openfire, Xcode, Prototyping, iOS SDK, Android, Architecture, Leadership, Mobile Development, Decentralized Systems, Networking, Full-stack, Software Development, REST APIs, APIs, Mobile Apps, Core Data, Core Bluetooth, Front-end, Agile Software Development, Data Structures, Mobile App Development, Technical Leadership, Database Architecture, Cloud, Online Payments, Consumer-facing Products, StoreKit, App Store, WebSockets, AVFoundation, Back-end, Identity & Access Management (IAM), PostgreSQL, Mobile, Apps, Coding, Software, 3D CAD, iOS Native Libraries, IoT Security, App Store Acceptance Process, RESTFul APIs, App Store Optimization (ASO), Software Architecture, Early-stage Startups, Messaging, Minimum Viable Product (MVP), API Integration, Security, Real-time Data, Real-time Systems, Wearable Technology, Wearables, HTML, Social Networks, Streaming, Microservices, Model View ViewModel (MVVM), Asynchronous Programming, GitHub, Growth, VPN, Heroku, WebRTC

Experience

Bank Millennium App

https://apps.apple.com/us/app/bank-millennium/id412646128
This is a customer-facing app that provides all the functionalities that the bank offers. My team implemented the main functionality, a full app version for children under 13. It was written in Swift and UIKit.

Cearch

Cearch is a GPS-based location technology that helps you find people and places from your phone. The app provides an arrow that points to the person or object of interest, which is useful, especially outside of an established road or path grid.

CareMate

https://apps.apple.com/us/app/comarch-caremate/id1450787539
CareMate is a mobile application that constitutes a part of a comprehensive care service offered by Comarch. The application, combined with an integrated Comarch WristBand monitoring device (available as a wristband or key ring), constitutes a modern remote care service dedicated to elderly and chronically ill people who need constant monitoring and support in care.

Transport GZM

https://apps.apple.com/pl/app/transport-gzm/id1658522203
Transport GZM is a free mobile application that helps you travel across 56 municipalities of Upper Silesia and the Dąbrowa Basin. The application allows you to plan and pay for your journey.

The application was created by the Upper Silesian-Zagłębie Metropolis, one of Poland's largest organizers of public transport.

System FALA

https://apps.apple.com/ph/app/system-fala/id1625883975
The System FALA application is one of the tools of the FALA System, enabling convenient and quick purchase of SKM and POLREGIO train tickets in the entire Pomeranian Voivodeship (includes tickets from the Pomeranian Tariff) and tickets for public transport in the Tri-City.

Education

2020 - 2023

Bachelor's Degree in Computer Science

Polish-Japanese Academy of Information Technology - Warsaw, Poland

2004 - 2006

Master's Degree in Computer Science

Warsaw University of Technology - Warsaw, Poland

Skills

Libraries/APIs

REST APIs, iOS Native Libraries, React, RxSwift, Node.js, WebRTC

Tools

Xcode, TestFlight, GitHub, Expo, Figma, VPN, GitLab CI/CD, WildFly, RabbitMQ

Languages

Swift, Objective-C, GraphQL, TypeScript, JavaScript, Java, Kotlin, Embedded C++, C++, Embedded C, CSS, HTML, Python

Frameworks

SwiftUI, Combine, React Native, iOS SDK, Core Data, Core Bluetooth, UIKit, Spring Boot, StoreKit, AppKit, Redux, NestJS

Paradigms

Mobile Development, Agile Software Development, App Store Optimization (ASO), Real-time Systems, Microservices, Model View ViewModel (MVVM), Asynchronous Programming, UI Design, Web Architecture, DevOps

Platforms

iOS, MacOS, Firebase, Mobile, Bluetooth Low Energy (LE), Android, Amazon Web Services (AWS), Apple Watch, Docker, Kubernetes, Heroku

Storage

JSON, Database Architecture, MongoDB, PostgreSQL, MySQL

Other

Software Development, Computer Science, Prototyping, User Interface (UI), User Experience (UX), Architecture, Leadership, Decentralized Systems, Networking, Full-stack, APIs, Mobile Apps, Front-end, Data Structures, Mobile App Development, Technical Leadership, Online Payments, Consumer-facing Products, Bluetooth, Back-end, Apps, Coding, Robotics, Software, App Store Acceptance Process, RESTFul APIs, Full-stack Development, Early-stage Startups, Messaging, Minimum Viable Product (MVP), API Integration, SMS, Security, Real-time Data, Wearable Technology, Wearables, Social Networks, Streaming, Data Visualization, Async/Await, Near-field Communication (NFC), CI/CD Pipelines, Cloud Infrastructure, Cloud, In-app Purchase (IAP), App Store, WebSockets, AVFoundation, OAuth, Identity & Access Management (IAM), Embedded Systems, IoT Security, Software Architecture, A/B Testing, Subscriptions, Growth, Exchanges, Openfire, 3D CAD

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