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AWS certified full-stack developer with extensive experience in creating scalable distributed web applications for large and small businesses. 👨‍💻 8+ years in programming 🎓 Master's degree in Computer Science 🛠️ My Expertise: - Front-End: React, JavaScript, HTML5, CSS3, jQuery, Bootstrap - Back-End: Node.js, Java, Kotlin - Databases: MongoDB, MySQL, DynamoDB - Version Control: Git - Cloud: AWS – certified developer Looking forward to connecting, Paul.

Hello! I’m Mikolaj, a full stack web and mobile app developer with 5+ years of experience building production ready mobile apps, SaaS platforms, MVPs, marketplaces, admin dashboards, and AI-powered applications. I specialize in React Native, Expo, Flutter, Swift, Kotlin, Next.js, Node.js, Firebase, Supabase, PostgreSQL, Stripe, RevenueCat, and AWS. I can help you build a new product from scratch, improve an existing MVP, fix bugs, optimize performance, or prepare your app for App Store and Google Play release. What I Can Help You With 📱 Mobile App Development Cross-platform iOS and Android apps using React Native, Expo, and Flutter, with native Swift/Kotlin integrations when needed. I handle architecture, UI implementation, API integration, testing, builds, and store submission. 💻 Web Apps & Admin Panels Modern web applications, dashboards, and SaaS platforms using React, Next.js, TypeScript, and Tailwind CSS. ⚙️ Backend Development Secure and scalable APIs with Node.js, Express, NestJS, Firebase, Supabase, and PostgreSQL. I build authentication, real-time features, subscriptions, chat, notifications, and admin systems. 💳 Payments & Subscriptions Stripe, RevenueCat, in-app purchases, subscription logic, webhook handling, and payment flows for mobile and web apps. ☁️ Deployment & DevOps AWS, Docker, GitHub, CI/CD, app store deployment, production configuration, bug fixing, and performance optimization. Project Types I Work On * MVPs for startups * SaaS platforms * AI-powered mobile and web apps * Marketplaces * Chat and social apps * E-commerce platforms * Booking and on-demand service apps * Internal business tools * Admin dashboards * Subscription-based apps Why Work With Me I take ownership of the full development process, from planning and architecture to launch. I write clean, maintainable code, communicate clearly, and focus on delivering a product that is stable, scalable, and easy to continue building on. I’m especially interested in long-term projects where I can help improve the product, add new features, and support growth after launch. ✨ Let’s build something reliable, modern, and ready for real users. Feel free to reach out and tell me about your project.

Job Title/Positions: iOS Team/Tech Lead, Senior iOS/Mac OS Developer, C/C++ software developer, C/C++ 2D game developer Summary of Skills * Experience in development using languages: Swift, Objective C, C/C++, Ruby, Java, Kotlin * Experience in development using frameworks: SwiftUI, Combine, Cocoa, Foundation, UIKit, RxSwift and other related reactive libraries, CoreData, GCD, OCUnit, cocos2d, OCMock, CocoaPods, SpriteKit, Android SDK, Rails * Experience in development using methodologies: Waterfall, TDD (writing both unit testing and automated UI testing), Scrum. * Experience in TCA and pattern oriented software development Miscellaneous * My primary goal is to get things done with acceptable quality. * I like to solve challenging tasks, especially tasks, which need to do some research. * I like to help team members in solving their tasks with minimum effort. * I like to work smarter, not harder. * I have the ability to learn new technologies quickly and work in a fast paced environment.

I'm a top-rated freelancer on Upwork with high-level developer skills for over 6 years. My nickname at lin.ked.in 'rusakovic' Main skills: React.js, React Native, Next.js, Firebase, PostgreSQL, Supabase, Node.js. I could do almost everything in Typescrpipt: from creating Telegram Bot to SaaS website. 1. I am a seasoned Full Stack Developer with a rich experience in building high-quality, scalable and SEO-optimized web applications. My expertise lies in React.js, React Native, Node.js, and TypeScript, and I have a proven track record of delivering robust solutions for various industries including fintech, food, and communication platforms. 2. I have had the privilege of working with diverse teams across the globe, from Tokyo, Japan to London, UK, and Berlin, Germany. My journey started with AVISIO, where I honed my skills in React, Redux, and TypeScript, creating and maintaining various components and pages. I then moved on to PATERS CO LTD, where I was instrumental in creating a dating app from scratch using React Native, transitioning from Swift/Kotlin to React Native. 3. At SORTEDfood, I was responsible for creating new screens and components, refactoring code, and transitioning React navigation from v1 to v6. I also implemented Redux Toolkit and wrote tests using Storybook, Loki, and Detox. My stint at Coder Society further solidified my skills in React.js and Node.js, where I worked on a fintech project. 4. At Nomo, I was involved in updating React Navigation from v5 to v6, transitioning TypeScript from v3 to v4, and integrating Google Pay. I also increased test efficiency with Appium and used GraphQL and Apollo for data caching and fetching. My most recent experience at Spencer involved adding share functionality, configuring Bitrise workflow for building iOS and Android apps, and improving documentation. 5. In addition to my professional experience, I have also created my own project, likeremote.com, using Next.js, Supabase database, and Vercel as a hosting provider. This site boasts a 100% SEO optimization score, demonstrating my ability to build SEO-friendly applications. 6. I am always eager to learn and adapt to new technologies and believe in continuous improvement. I am confident that my skills and experiences make me a strong candidate to provide high-quality development services. I look forward to the opportunity to contribute to your team and projects.

✋ Representing Sixhands agency I am a highly skilled player with app and web development competencies and 8 years of experience in the industry. I have a deep understanding of the latest technologies and best practices in app and web development, and I am committed to delivering high-quality solutions that meet my clients' specific needs. My expertise includes developing custom apps for iOS and Android, building responsive and user-friendly websites, and integrating various APIs and third-party tools. I also have experience with e-commerce platforms, CMS systems, and database management. My approach to work is client-centric, and I strive to ensure that my clients are satisfied with every aspect of the project. From the initial consultation to the final product launch, I work closely with my clients to ensure that their vision is realized! In addition to my technical skills, I am a great communicator and collaborator. I believe that clear communication is key to successful projects, and I work closely with my clients to ensure that we are always on the same page. If you are looking for a reliable and talented app and web developer who can deliver exceptional results, look no further. Contact me today to discuss your project! If you are looking for a reliable and talented freelancer who can deliver exceptional results, look no further. Contact me today to discuss your project!

I've been working as Android Team Lead for 7 years. I have strong experience in team management, team supporting and mentoring. Has grown specialist from Junior to Senior. Can manage team resources and dedicate an appropriate team member to a project. At the same time, I'm a developer and have strong Java and Kotlin knowledge. I've worked on Android application where cryptography was used. Well experienced in application development for banks and credit organizations. Worked on multimedia projects like audio players, trains schedule. Good knowledge in code review, know and use Java/Kotlin best practices and development patterns, follow Clean architecture and can create a stable and reliable application for your business and clients. I possess the following technical skills: Android skills: Activity, Fragments, ContentProviders, Services, Multithreading Frameworks: Retrofit, Dagger2, Room, Navigation and etc. Languages: Kotlin, Java Additional Software: Git, Jira. Methodology: Scrum, Agile