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I build production-ready mobile apps and backend systems that are clean, scalable, and easy to maintain. I'm a Full-Stack Engineer with 4+ years of experience delivering Flutter apps and Python (FastAPI) APIs used in production. I help founders and teams ship reliable software, not fragile prototypes. Services Flutter (iOS & Android) Pixel-perfect UI, responsive layouts, animations, state management (Riverpod/Bloc), offline support, and real-time features. Python / FastAPI Secure REST APIs, auth (JWT/OAuth), background tasks, pagination, rate-limiting, and third-party integrations. ETL & Integrations API ingestion, data cleaning/validation, and structured exports (JSON/CSV). Why Clients Hire Me - Apps that feel polished and production-ready - Backends that scale and are easy to maintain - Clear communication and predictable delivery How I Work Clear communication, short feedback loops, clean code, and proper handover documentation. Tech Stack Flutter · Dart · Python (FastAPI) · PostgreSQL · MongoDB · Docker · Firebase · CI/CD

I help startups and enterprises build fast, scalable 𝐒𝐚𝐚𝐒 platforms and 𝐀𝐈-𝐢𝐧𝐭𝐞𝐠𝐫𝐚𝐭𝐞𝐝 applications. With 8+ years of experience across the full stack, I specialize in clean architecture, secure APIs, and production-ready infrastructure. I don't just write code; I help you plan, build, and scale your product from MVP to production. 𝑻𝒆𝒄𝒉𝒏𝒊𝒄𝒂𝒍 𝑺𝒕𝒂𝒄𝒌: 𝗙𝗿𝗼𝗻𝘁𝗲𝗻𝗱: React.js, Next.js, Vue.js, Angular, Svelte, Tailwind CSS, Material-UI, GraphQL. Focus on reusable components, responsive design, and modern UI frameworks. 𝐁𝐚𝐜𝐤𝐞𝐧𝐝: Node.js, Express, NestJS, REST APIs, Microservices, JWT/OAuth, WebSockets. Emphasis on secure architecture patterns and real-time data handling. 𝐃𝐚𝐭𝐚𝐛𝐚𝐬𝐞𝐬: PostgreSQL, MySQL, MongoDB, Firebase, Supabase, DynamoDB, Redis. Optimized for speed, indexing, and high-scale data management. 𝐂𝐥𝐨𝐮𝐝 & 𝐃𝐞𝐯𝐎𝐩𝐬: AWS (Lambda, S3, RDS, Cognito, AppSync), Docker, Terraform, Infrastructure as Code (IaC). CI/CD automation with GitHub Actions & AWS CodePipeline. 𝐓𝐞𝐬𝐭𝐢𝐧𝐠 & 𝐓𝐨𝐨𝐥𝐬: Jest, Cypress, Playwright (E2E Testing), Web Scraping (Puppeteer, Cheerio), Google Analytics, Sentry, and Real-time Monitoring. 𝗠𝘆 𝗖𝗼𝗿𝗲 𝗙𝗼𝗰𝘂𝘀: 𝐀𝐈 & 𝐒𝐚𝐚𝐒 𝐏𝐥𝐚𝐭𝐟𝐨𝐫𝐦𝐬: Architecting backends for heavy-data applications (e.g., AI audio processing, EdTech) without compromising performance. 𝐏𝐞𝐫𝐟𝐨𝐫𝐦𝐚𝐧𝐜𝐞 & 𝐑𝐞𝐥𝐢𝐚𝐛𝐢𝐥𝐢𝐭𝐲: Optimizing database queries, ensuring low-latency frontend rendering, and writing clean, maintainable code. Let’s talk about how I can help take your project to the next level.

Over 20 years of experience in tech. My most recent work: - ETL to upload Excel Financial Reports, then process and consolidate them into fit for purpose regulatory reports. - IoT Data Ingestion into S3, then process the data using event driven architecture in AWS, finally creating emailed reports to send to users. - SaaS platform that I built and own called Nopaque. Automates the testing of organisations telephony services, by mapping journeys, testing paths and performing function/load tests. - RantClub, a small experiment and fun website to showcase Deepgrams APIs and how they can be used to classify and summarise transcripts. Before this most recent work (last 2 years). I was the Director of Engineering for over 100 staff and remained hands on 'in the moment'. Prior to this, I was a CTO that lead a team of about 60 and had influence over the wider organisation. I participated in multiple MVP builds, two of which eventually went on to become offerings that increased our company value by over 60% before sale. - The first was engineering and delivery of Amazon Connect, with utilities/tools that we could drop in and accelerate adoption of the technology. In this role I worked with 3 large UK banks. - The second was our approach to MLOps - in which we were able to begin the journey for a major UK bank who are now considered one of the leaders in this space. During and prior to this, I was a full time Cloud Architect/Engineer - having held all 5 core AWS exams between 2016 - 2020.

Hello, my name is Serhii, I'm blockchain Fullstack developer with 5+ years of experience developing web, desktop applications. Recently working with blockchains (e.g. Ethereum) and its ecosystems as Blockchain Fullstack Developer. Solidity (Ethereum smart contracts: ERC20, ERC1155, ERC721), Typescript Technologies: .NET, React + Redux (Web2, Web3), Node JS (Nest JS/ Express JS) .NET - C# (Web API, ASP.NET MVC, Blazer, Web3, WPF) Cryptography, The Graph, GraphQ, Azure, AWS, Google Cloud platform, Time management, Communication Team work, Attention to details, Attention to details, Optimism, Self-motivation, Imagination Databases: SQL/noSQL, DBs Source Controls: Git, GitHub, GitLab, Azure pipelines Tracking Systems: Jira Buzzwords: Blockchain Technologies Ethereum ERC-20 NFT ERC-721 ERC-1155 TheGraph Solidity Tenderly Moralis Infura Alchemy Hardhat Decentralized Applications DApps Waffle TypeChain Web3.js Ethers.js Golang Oracles Hyperledger Fabric Chainlink Uniswap Layer 2 Smart Contracts Solidity Chaincode Front-end TypeScript JavaScript React.js Next.js Vue Svelte Redux Cypress Mocha Ethers.js Web3.js Wagmi.js Firebase Back-end Node.js Next.js Nest.js Golang C++ Rust Azure Cryptography Security Public Private Key Infrastructure Zero-knowledge proof Encryption Ethernaut - OpenZeppelin API Integration REST API WebSocket GraphQL Databases MongoDB MySQL Supabase Firebase Database DevOps Docker CI/CD Ubuntu Shell Scripts Make Scripts designer desiner U / UX Designs Web App Site UX/ UI SaaS Figma Re-Design Ux mobile Needed Application Expert Product projects Need Wireframe B2B Mockup Prototype Platforr Existing Portal Talented Create Dashboard Required Looking New Develop Modern Conversion Build Finance Content Software Screens Graphic Brand interactive Android Help Homepage Marketplace High-Fidelity Frontend Fashion Medical MVP short longer term Work Research Information Architecture U/X Revamp Supplement Start-Up entertnment Chatbox Monitoring Conversational Integration Review Interface Flow Gaming CRO Set Big Driven E-Learning Fintech Need Skills multiple Long-term Commerce App Design Healthcare Sector Seeking Services broad Custom Unique UX-Centric Vision Full Creative Create B2C Lead Innovative User Journey Audit Optimization User interface Evolve Concept Upgrade Data Analytics UI UX UX UI UI iOS Mock ups Modernize Minimalist Game Conversion Rate Experienced Travel Innovative Senior Startup Health Generative Team Company Specialist Ui ux Portals Modernization Refresh Minimalistic Conversion-focused Building Ul / UX UX/UI Redesign Mockups Mock Up Mock-up Prototyping landing page UI/UX App Redesign Interactive Digital Product Mobile Ul User Interface Figma Expert Mockup Interactive Mockup User-Centered Custom Web Navigation System Adobe XD Expert UI Animation UX Wireframe GUI Webflow JX & Ul Mobile App Mobile Ul Desktop Application Web Application UI/UX Prototyping User Experience Figma App iPhone UI Android UI UX Wireframe Wireframe iPadOS Software Responsive Usability Testing & Usability Research Competitive Analysis Interaction Journey Mapping User Experience Strategy Information Architecture Research Documentation User Flow High Fidelity Mobile App Redesign Prototyping Wireframing Icon Mockup Style Guide Android iOS watchOS UIKit Layout User-Centerec Custom Web Platform SaaS Ul Graphics Product JI Animation Web Application Audit Dashboard Concept Mobile Angular iPad Ul Minimum Viable Product Concept UI/UX UI UX design User Interface Promo Adaptive User Interface platform design Landing Page Responsive Graphics & Ul Website User Experience InVision Axure Responsive Hire Webflow Infographics design UX/UI Desktop Sketch Adobe WordPress Experienced logo design Technology & IT Entertainment Business & Sales Marketing Advertising B2B B2C Consultancy Science Sport & Wellness Fashion & Beauty Apparel Nonprofit Startup Transport & Logistic Education Arts & Culture Design & Architecture Hospitality & Leisure Manufacturing Food & Drinks Travel Law SaaS DaaS Home Services Banking & Finance Real Estate Luxury Retail Healthcare & Medicine Professional Services Startup Start-up Small & Midsize

🌟 Expert Mobile App & Web Developer | iOS, Android, Flutter, Laravel | 10+ Years of Proven Success 🌟 Hello! I’m a seasoned mobile and web developer with over a decade of expertise in crafting high-performance applications and websites that deliver exceptional user experiences. Specializing in iOS, Android, Flutter, and Laravel, I build scalable, maintainable solutions that drive growth and engagement for clients worldwide. What sets me apart? - Full-Stack Capability: Skilled in both frontend and backend development, I handle the full cycle of web and mobile projects, from UI/UX to server-side logic, database design, and seamless API integrations. - Clean, Flexible Code: Known for writing testable, modular code, I adhere to SOLID principles and industry best practices, ensuring efficient, maintainable, and robust applications. - Cross-Platform Expertise: Experienced in creating hybrid and native mobile solutions, as well as feature-rich websites, I bring versatility and depth to every project. Technical Skills: - Mobile Development: Native Android development, Native iOS development, Hybrid app development, Swift, SwiftUI, UIKit, Combine, Java, Kotlin, Flutter, Dart - Web Development: Laravel, PHP, HTML, CSS, JavaScript, Vue.js - Backend & API Integration: RESTful APIs, GraphQL (Apollo, AWS AppSync), Firebase, AWS, MySQL - Database & Server Management: MySQL, MongoDB, AWS, DigitalOcean - Payment Integration: Stripe, Apple Pay, Google Pay, PayPal, In-app purchases - CI/CD & Testing: AppCenter, PHPUnit, TDD, XCTest, unit and integration testing - Tools & Collaboration: Git, Jira, Postman, Figma, Charles, Proxymen I am dedicated to understanding your business needs and delivering tailored solutions that captivate users and drive success. Whether you're looking for a powerful mobile app, a dynamic website, or a robust backend, let's connect and bring your project vision to life!

Senior Android Developer | Kotlin + Jetpack + Firebase + AI | SaaS • HealthTech • Finance Apps 👋 Hi! I’m a highly experienced Android developer and AI engineer with a Bachelor’s in Software Engineering and a Master’s in Artificial Intelligence from the University of Essex, UK. With a deep passion for clean architecture, cutting-edge UI, and scalable backend integration, I bring years of real-world expertise in delivering production-grade mobile apps across industries — including logistics (Click & Collect), healthcare, and finance. Android Development Expertise: As the Lead Developer of Opus, a custom-built Click & Collect logistics app for VJ Technologies Ltd United Kingdom, I built and maintained a modern, high-performance Android app with: 1. Kotlin & Jetpack (Compose, Navigation, ViewModel, LiveData, Coroutines) 2. MVVM + Clean Architecture for scalable, maintainable code 3. Modular codebase with single-activity architecture using NavHostFragments 4. Complex RecyclerViews, diff utils, and view binding for responsive UIs 5. Image handling with Coil, smart preloading, and error-safe loading states 6. Optimized memory management to avoid leaks and ensure smooth performance 7. Camera management, ai model ONNX integration, facial detection (eye, nose, hands) reaction data extracting using Machine Learning. ✅ Integrated full offline/online state handling, clean separation of UI and domain layers, and robust background job handling for syncing and status updates. ☁️ Backend & API Skills 1. Retrofit + Moshi/Gson for clean, async API integration 2. Firebase (Firestore + Auth + Cloud Functions) for real-time, secure apps 3. AWS Lambda + API Gateway usage for serverless logic and secure endpoints 4. Full error handling with Snackbar/Toast, HTTP status mapping, and retry policies 5. Secure user authentication (Firebase Auth & OAuth2) and encrypted session storage 🧠 AI & HealthTech Projects With a strong academic background in AI, I conducted real research in neurological disease early detection: 1. Developed an AI-driven system for Alzheimer’s detection using MMSE scoring models and natural language interaction 2. Built mobile-first prototype apps that analyze speech, responses, and patterns using ML models for risk scoring 3. Worked with structured medical datasets and integrated with AI pipelines (classification, NLP, risk prediction) 💰 Finance & Productivity Apps I’m also the creator of FlexyMint, a smart personal finance & budgeting app for small business owners. Built using Kotlin with Firebase, it includes: 1. Multi-account syncing 2. Daily/monthly budget breakdowns 3. Local + cloud data storage 4. Real-time analytics with charting 🚀 What Sets Me Apart 1. Clean, scalable code with architecture that’s built for real-world growth 2. Deep experience in both UI/UX and backend/API integration 2. Performance-first mindset — optimized RecyclerViews, memory-safe ViewModels, smart image loading 3. Experience building apps that serve real customers, not just prototypes 4. Fluent in Kotlin, Jetpack Compose, and modern Android design systems 5. Comfortable with agile collaboration, Git, CI/CD, and long-term maintenance 🎓 Education 🎓 Master’s in Artificial Intelligence – University of Essex, United Kingdom 🎓 Bachelor’s in Software Engineering – IIU Kotlin, Android, Jetpack Compose, MVVM, Clean Architecture, Firebase, Firestore, Firebase Auth, Retrofit, Coroutines, RecyclerView, Coil, Navigation Component, Jetpack ViewModel, LiveData, QR Code Scanning, CameraX, Barcode Scanner, ML Kit, Google Face Detection, Biometric Login, AI Mobile Apps, Machine Learning, TensorFlow Lite, MMSE Testing, HealthTech, Alzheimer Detection App, FinTech App, Budget App, SaaS App, Click and Collect, Kotlin Expert, Android Performance Optimization, Memory Leak Prevention, Secure Login, Modular Android, Android Jetpack, REST API Integration, Google Play Publishing, Agile Development, Git, MVVM Android, Firebase Realtime, Smart UI/UX, Cross-Device Compatibility, Android Clean Code