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Hi, I’m Grzegorz Makowski, a highly motivated Senior iOS Developer with over 8 years of experience designing, building, and maintaining innovative mobile applications. I am proficient in Swift and Objective-C, with hands-on experience integrating RESTful APIs, optimizing performance, and delivering scalable solutions. I enjoy collaborating with cross-functional teams to create clean, maintainable code and outstanding user experiences. I also have a foundational understanding of cross‑platform development using Flutter and basic Android development skills, which helps me contribute to multi‑platform discussions and architecture strategies. I believe that maintaining a unified user experience across platforms elevates overall product quality and simplifies maintenance.…Hi, I’m Grzegorz Makowski, a highly motivated Senior iOS Developer with over 8 years of experience designing, building, and maintaining innovative mobile applications. I am proficient in Swift and Objective-C, with hands-on experience integrating RESTful APIs, optimizing performance, and delivering scalable solutions. I enjoy collaborating with cross-functional teams to create clean, maintainable code and outstanding user experiences. I also have a foundational understanding of cross‑platform development using Flutter and basic Android development skills, which helps me contribute to multi‑platform discussions and architecture strategies. I believe that maintaining a unified user experience across platforms elevates overall product quality and simplifies maintenance.

Grzegorz Makowski

App Developer, Front-End Developer, Back-End Developer, +3

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Hi, I’m Grzegorz Makowski, a highly motivated Senior iOS Developer with over 8 years of experience designing, building, and maintaining innovative mobile applications. I am proficient in Swift and Objective-C, with hands-on experience integrating RESTful APIs, optimizing performance, and delivering scalable solutions. I enjoy collaborating with cross-functional teams to create clean, maintainable code and outstanding user experiences. I also have a foundational understanding of cross‑platform development using Flutter and basic Android development skills, which helps me contribute to multi‑platform discussions and architecture strategies. I believe that maintaining a unified user experience across platforms elevates overall product quality and simplifies maintenance.…Hi, I’m Grzegorz Makowski, a highly motivated Senior iOS Developer with over 8 years of experience designing, building, and maintaining innovative mobile applications. I am proficient in Swift and Objective-C, with hands-on experience integrating RESTful APIs, optimizing performance, and delivering scalable solutions. I enjoy collaborating with cross-functional teams to create clean, maintainable code and outstanding user experiences. I also have a foundational understanding of cross‑platform development using Flutter and basic Android development skills, which helps me contribute to multi‑platform discussions and architecture strategies. I believe that maintaining a unified user experience across platforms elevates overall product quality and simplifies maintenance.

Available to hire

Hi, I’m Grzegorz Makowski, a highly motivated Senior iOS Developer with over 8 years of experience designing, building, and maintaining innovative mobile applications. I am proficient in Swift and Objective-C, with hands-on experience integrating RESTful APIs, optimizing performance, and delivering scalable solutions. I enjoy collaborating with cross-functional teams to create clean, maintainable code and outstanding user experiences.

I also have a foundational understanding of cross‑platform development using Flutter and basic Android development skills, which helps me contribute to multi‑platform discussions and architecture strategies. I believe that maintaining a unified user experience across platforms elevates overall product quality and simplifies maintenance.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Intermediate

Intermediate

Language

English

Advanced

Polish

Fluent

Work Experience

iOS Developer at Millennium Bank

March 1, 2019 - Present

Developed mobile applications by writing new code and optimizing existing ones. Migrated legacy Objective-C code to Swift, improving maintainability and reducing technical debt. Collaborated with cross-functional teams (backend, designers, QA) using Agile methodologies to deliver projects on time. Conducted thorough code reviews to ensure adherence to best practices, clean coding standards, and maintainability.

iOS Developer at Booksy

February 1, 2019 - September 9, 2025

Worked on two apps: one for clients to book appointments and another for salons to manage their schedules. Programmed in Swift, developed new features and maintained existing modules. Initiated reusable UI components to streamline development and maintenance. Integrated with RESTful APIs, optimized performance, and implemented push notifications. Participated in code reviews and collaborated with backend and UX/UI designers to ensure app stability.

iOS Developer at Booksy Customer

February 1, 2018 - September 9, 2025

Contributed to the Booksy Customer app by creating reusable UI components, integrating with RESTful APIs, and focusing on performance and stability.

iOS Developer at United Ideas

August 1, 2017 - September 9, 2025

Designed and developed iPhone/iPad apps, creating, extending and maintaining features for iOS platforms.

Java Developer at Center for Informatics Technology

June 1, 2015 - September 9, 2025

Java development including Java 8, EJB 3, Spring Data, Hibernate, PrimeFaces 5.0, and SOAP Web Services.

iOS Developer at Millennium Bank

March 1, 2019 - Present

Developed mobile applications for iOS using Swift and Objective-C, migrated legacy Objective-C code to Swift, and optimized performance for a high-traffic banking app. Collaborated with cross‑functional teams (backend, designers, QA) to deliver scalable solutions and conducted thorough code reviews to maintain quality and maintainability.

iOS Developer at Booksy

February 28, 2019 - September 9, 2025

Worked on two Booksy apps: one for clients to book appointments and another for salons to manage schedules. Programmed in Swift, created reusable UI components, integrated with RESTful APIs, implemented push notifications, and participated in code reviews with backend and UX/UI teams.

iOS Developer at Booksy - Booksy Customer

March 1, 2018 - September 9, 2025

Developed a modular, reusable, well-documented SDK enabling seamless identity verification via document submission, including ID photos. Focused on creating a modular SDK that could be easily adopted by multiple apps.

iOS Developer at Unified Ideas

August 1, 2017 - September 9, 2025

Designed and extended iOS applications for iPhone/iPad, contributing to cross‑platform development and building reusable UI components, MVVM architecture, and robust collaboration with backend/UX teams.

iOS Developer at PKO Bank Polski

August 1, 2017 - September 9, 2025

iOS development for a major banking app, focusing on secure user experiences, performance optimization, and coordination with backend teams to deliver reliable financial solutions.

iOS Developer at IT MAGINATION

February 1, 2016 - September 9, 2025

Developed iOS applications, built modular code and SDKs for user identity verification, and contributed to reusable, well-documented solutions adoptable across multiple apps.