I ❤️ solving iOS problems - big and small. You can hire me to fix a bug, implement a complex feature, integrate ChatGPT or other services or frameworks, implement a design, or write a whole new mobile app from scratch. WHAT I OFFER • I prefer setting clear milestones from the beginning of the project and delivering on time. • Communication is a top priority for me, I post regular updates on my progress. • I write top-quality, maintainable, and robust code. • I freelance full-time, and you have my full attention on your project. EXPERIENCE I’m a seasoned iOS developer with 12 years of experience making 5-star-rated apps for the iPhone, iPad, and Apple Watch. In my previous role as a full-time senior developer, I was responsible for the development of business and productivity apps - document processing, cloud storage, and online collaboration. Before I fell in love with iOS I had 10 more years of experience developing mobile applications for Symbian, Palm, and Windows Mobile. I am familiar with most standard iOS APIs such as UIKit, Foundation, SwiftUI, Combine, animations, in-apps, push notifications, MapKit, StoreKit, StoreKit 2, Sign In with Apple, etc. I can help with App Store Review guidelines and issues. I’ve used many third-party frameworks like Firebase, AdMob, Facebook SDK, Flurry, AppsFlyer, etc. Dev tools: Xcode, Git, Figma, Jira, Trello, TestFlight, Jenkins. Don’t hesitate to drop me a message. I’d love to discuss your project.

Ready to take your Website or Mobile App into the future? Whether it's developing an intuitive user interface or creating an attractive and functional website, I can help you design and develop your next digital product from scratch as well as update your existing one so it's optimized for today's users and tomorrow's trends. I will work with you to create a unique experience that captures your brand voice and story, making it easy for people to find what they need quickly and enjoyably. What tools do I use? 
➡️ Adobe XD, Figma and Moqups [Wireframes/Mockups] ➡️ Adobe Photoshop and Illustrator [Image and Vector Editing] ➡️ Final Cut, Adobe Premier Pro & Adobe After Effects [Video Editing] ➡️ Webflow & Shopify [Development] Why choose me? 

✅ Dedicated: I want my clients to be proud of their website and I always give my best to exceed expectations.
 ✅ Responsive: I make sure to discuss every point of the development process in fluent English so that the end result is effective for the project's needs.
 ✅ Professional: I always try to have a pleasant conversation and do not mind providing additional information or development options outside the scope of the contract. Let's connect!

I’m a front-end web developer focused on building modern, responsive, and visually clean websites that help clients present their ideas professionally online. I work with HTML, CSS, JavaScript, and React to create interfaces that are user-friendly, well-structured, and optimized for different screen sizes. I can help with landing pages, portfolio websites, business websites, website redesigns, and front-end web applications. I enjoy turning designs and ideas into functional websites that look polished and feel smooth to use. My focus is always on clean layouts, responsive design, clear structure, and a strong overall user experience. I pay attention to detail, write organized code, and work carefully to make sure each project matches the client’s goals. I can also help improve existing websites by fixing styling issues, adjusting layouts, improving responsiveness, and making the interface feel more modern and professional. I’m reliable, easy to communicate with, and serious about delivering quality work on time. I follow instructions closely, stay open to feedback, and aim to make the process simple and stress-free for clients.If you need a developer who is motivated, detail-oriented, and ready to build a clean, responsive, and professional website, I’d be happy to help bring your idea to life.

🚀 Full-stack fitness and AI products built to feel sharp, reliable, and ready for real users - React dashboards, Python APIs, computer vision workflows, OpenAI features, coaching tools, progress tracking, and clean delivery without engineering drama. I build web platforms where product experience and backend reliability matter at the same time. That usually means taking a rough idea, prototype, Figma file, legacy app, or half-working MVP and turning it into a product people can actually use. My strongest fit is full-stack development for fitness, wellness, coaching, sports-tech, and AI-assisted products. I can own the frontend, backend, database, integrations, admin tools, and deployment flow, while also understanding the product details that make these apps different: workout plans, exercise libraries, progress charts, body metrics, video or image-based form checks, trainer workflows, subscriptions, bookings, notifications, and member dashboards. A few examples of the kind of work I deliver: I shipped a fitness coaching web platform with coach and client dashboards, workout scheduling, progress tracking, subscription flow, and admin tools. The goal was not just to "build screens." The goal was to make daily coaching work easier, keep the data clean, and give the client a product they could improve after launch. I built AI-assisted product features around structured data, document parsing, recommendations, and workflow automation. Instead of treating AI as a magic button, I connect it to real product logic: user permissions, review steps, logging, retries, fallback states, and clear UI controls. I worked on computer vision features using Python and OpenCV for image processing, object detection support, measurement workflows, and visual data extraction. For fitness or sports products, this can support form review, movement analysis, exercise media processing, and smarter trainer tools. How I work is simple and practical. You get a clear technical plan before heavy development starts. I break the work into small releases, keep the scope visible, and give regular async updates so you are never guessing what is happening. I prefer working software over long theory. You see progress early, test it early, and we adjust before expensive mistakes pile up. I write code that another developer can continue. That means clean component structure, readable backend services, typed APIs where useful, database migrations, tests for critical logic, and documentation for setup, deployment, and handoff. I do not hide messy code behind a nice demo. I care about communication because most software problems are not only code problems. If a feature has a risk, I say it early. If a simpler solution will save money, I will recommend it. If your current idea needs a better technical path, I will explain the tradeoff clearly. What I build: Full-stack web apps, AI-powered dashboards, fitness coaching platforms, admin panels, client portals, computer vision tools, API integrations, payment flows, scheduling systems, data dashboards, MVP rebuilds, and feature upgrades. Core stack: JavaScript, TypeScript, React, Next.js, Node.js, Python, FastAPI, Django, OpenAI API, Computer Vision, OpenCV, REST API, PostgreSQL, MongoDB, Supabase, Firebase, Stripe, Docker, AWS, Tailwind CSS, GitHub, CI/CD. Good-fit projects for me: Fitness or wellness web platforms that need more than a basic landing page. AI features that must connect safely with real users, workflows, and business rules. Computer vision or image-processing features for movement, media, measurement, or automation. Existing React or Python products that need cleanup, new features, better architecture, or a reliable developer who can take ownership. If you have a fitness product, AI workflow, CV feature, or web app that needs a practical senior developer, send me the brief. I can help you shape the scope, avoid overbuilding, and move the product forward with clean, maintainable work.

During my years of working as a software engineer I have gained knowledge with multiple technologies and have a solid technical foundation. I am currently working as a techincal project manager and as an operations engineer in a large German bank where I am primarily responsible for ensuring application uptime and stability but I also troubleshoot and resolve various technical issues across different areas. My experience includes automation with Python, API testing via Postman, monitoring with Dynatrace, Kibana, and Grafana, and developing C-based load testing scripts using VuGen (LoadRunner). I’m taking my first steps toward a career in DevOps, supported by a solid foundation and a DevOps Foundation certification from the DevOps Institute (passed with distinction). I speak English and German very fluently (C1 level) and Bulgarian is my mother tongue. I’m currently available for part-time projects that align with my skills and experience.

I am a seasoned full-stack web developer with expertise in both traditional web2 technologies and cutting-edge web3 technologies. With a strong background in frontend and backend development, I excel in creating dynamic and responsive web applications. My skills include but are not limited to HTML, CSS, JavaScript, React, Nestjs and PostgreSQL. Additionally, I have hands-on experience with blockchain and decentralized applications, making me well-versed in the web3 landscape. I am committed to delivering high-quality solutions that meet client requirements and stay abreast of the latest industry trends to provide innovative and efficient web development services. Let's collaborate to bring your web projects to life!

I am a driven Software Engineering student and dedicated developer, experienced in building modern web applications, backend Java systems and mobile applications.

Hi, I’m Konstantin 👋 , a results-driven software engineer who helps startups ship secure, high-performance services and products - fast. My Experience? 👀 - 4+ years building Java production systems at Tide (fintech, 500 k+ users) and AI Agents at Mandel AI (YCombinator backed start-up) - Expert in Java 17 / Spring Boot 3 and equally comfortable delivering with Python or TypeScript/Node when the product demands rapid iteration - Twice awarded “Top Performer / Exempler” for delivering mission-critical APIs on time - Ranked Top 30 worldwide in SecureFlag secure-coding tournaments Why Hire Me? 💪 - Startup Mind-Set & Adaptability – I ramp up quickly, switch stacks when needed, and deliver tangible value in weeks, not months. - Business-First Engineering – every technical choice is driven by product goals (speed-to-market, cost, scalability). - Communication – daily/weekly updates, proactive risk flags, and no surprises. - Future-Proof Code – readable, tested, and documented so your team can pick up where I leave off I might be new in Upwork, but I am not new to shipping software! So.. 👉 If you need a partner who treats your product like their own—whether that means optimizing a Java microservice or whipping up a Python prototype—let’s chat. Click "Invite" and lets crush it together! 🚀

I am a final-year software engineering student and full-stack web developer focused on ASP.NET Core, Spring Boot, React, REST APIs, and database-backed web applications. I have practical experience building backend systems with authentication, validation, database integration, structured API endpoints, and clean layered architecture. I also work with React, TypeScript, and Next.js for frontend interfaces that communicate with backend APIs. My experience includes ASP.NET Core Web API, Java Spring Boot, React, TypeScript, Entity Framework Core, Spring Data JPA, PostgreSQL, SQL Server, Docker, RabbitMQ, and JWT authentication. I can help with backend API development, frontend-backend integration, bug fixing, dashboard/admin panel features, CRUD functionality, and improving existing web applications. I care about clean, understandable, and maintainable code, and I communicate clearly during development.

I build and optimize Shopify stores that look premium, load fast, and work flawlessly. My core focus is Shopify theme development and e-commerce web design: Liquid + JavaScript + HTML5/CSS, with a modular approach using Web Components to keep features encapsulated and maintainable. I regularly extend and refactor marketplace themes, implement custom functionality, and integrate third-party apps and systems while protecting performance and minimizing conflicts. Typical projects I deliver: Custom Shopify sections and theme modules (scalable + reusable) Theme upgrades and safe customization of marketplace themes App troubleshooting (conflicts, broken UI, cart/checkout issues, script collisions) Shopify Flow automations for ops workflows Front-end testing/QA to ensure consistent behavior across devices/browsers If you want a developer who understands both the Shopify ecosystem and real-world store operations — and can take ownership from diagnosis to final fix — let’s work.