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Hi👋 Will help you as a Java / Cloud architect, senior developer, and team lead with over 21 years of experience in the area (more than 150 projects delivered). We focus on RELIABLE software, and mission-critical operations, for which we use custom reliability technology for software (EDC), to prevent business downtime. I can help you with: • Cloud applications, scalable systems, • AI and LLM integration and development, • API design, development and integration, • High load/data volumes, predictive analytics, • Software for robots and machinery, • Internet of Things (IoT), • Reliable, safety and mission-critical systems. I EARN/SAVE MONEY💰 FOR OUR CUSTOMERS by: • allowing their business to expand (or start sometimes:) • automating processes and reducing operational cost • using newer and more efficient technology • long-run cost reduction because of high-quality software. Don't take my word for it, please review my profile feedback. Some techs below... ✅ Cloud applications Cloud, serverless, scalable applications, architecture and development for Amazon Web Services (AWS) and Google Cloud Platform (GCP). ✅ AI development and integration Embed AI-powered tools to your business and software: AI analytics, predictive maintenance, LLM, chatbots, ChatGPT integration, AI over your data helping your clients. ✅ Complex system development, API integration and development Develop custom software from A to Z, build sophisticated APIs, integrate third-party APIs, data hubs and gateways. ✅ Big data volumes processing, storage, and analytics Receive, process, store and analyze and send huge volumes of data. Cost-efficient data-focused systems on the cloud. ✅ Internet of things (IoT) Connect and manage thousands of simple and complex devices on the cloud, custom automation, reports and analytics. ✅ Other Workflow automation, Performance optimization, QA automation. Some tech details: ✓ Java: Java 8 and further versions, Spring, JavaEE, JavaFX ✓ Spring: SpringBoot, Spring MVC, Spring Security, Spring Data, ... ✓ Cloud: AWS, Google Cloud, Docker, Kubernetes, ECS, EKS, Cloud-native apps, scalable clusters, zero-downtime deployment. ✓ AI: ChatGPT, LLM, Vertex AI, Chatbots. ✓ Databases: Oracle/PostgreSQL/MySQL, big volume storage (AWS Redshift, AWS Athena/S3, Aurora, Cassandra, HDFS), Redis, MongoDB, Neo4j. ✓ Web: Bootstrap, Angular, React, JavaScript, OAuth, Tomcat, JBoss. ✓ APIs: REST, SOAP, XML-RPC, WebServices, WebSockets, Swagger/OpenAPI 3 etc. ✓ AWS: Clusters, AWS EC2, AWS Kinesis, AWS Athena, AWS Redshift, AWS DynamoDB, AWS Lambda, AWS IoT, AWS SQS/SNS, AWS CloudFront/Route53/ApiGateway, vast AWS API usage, and automation. ✓ Data streaming: AWS Kinesis, Firehose, SQS/SNS, Kafka, Camel, RabbitMQ. ✓ Performance optimization: JMeter, JProfiler, AWS X-Ray, GTMetrix, Gatling. ✓ Version control: Git, Github, Bitbucket, GitLab, SVN. ✓ CI/CD: Bamboo, Jenkins, Circle CI, Sonar, Bitbucket pipelines, AWS CodeBuild/CodeDeploy. ✓ Other: Maven, Nexus, Gradle, Ant. I get things done.

✅ .NET Full Stack Developer 20+ years of experience ✅ Build powerful .Net solutions that drive business growth ✅ C# .Net developer with 15+ years of experience ✅ Developed 50+ applications ✅ Crafted 200+ user-friendly interfaces that drive real business results. The clients say "It doesn't feel like outsourcing, but instead like we have our own remote developers." "They had great soft and hard skills and were full of ideas and drive!" I lead the fullstack and mobile development team at Itexus, a professional software development and consulting company focused on Fintech, Insurance, Healthcare, etc. I have 20+ years of experience in the .net architect development of web and mobile applications, .net, python, node.js, java developer as well as javascript, react .net, angular, AI frameworks and libraries. 👨‍💻.NET Full Stack Expertise .NET full stack – strong background in End-to-end development from database to UI using Microsoft stack .NET Core – deep expertise, cross-platform backend services .NET Angular – Full stack development on .NET backend and Angular frontend for enterprise-grade solutions .net core angular – Building complete systems with seamless backend–frontend integration .NET Core Angular – Scalable and secure web apps using .NET Core and Angular Angular .NET solutions – Using Angular for UI and .NET for API and business logic .net core developer – Proven experience delivering high-performance backend solutions using .NET Core .net core react – Building robust, scalable web applications with .NET Core APIs and React frontends c# .net developer – End-to-end development expertise using C# and the .NET ecosystem c# .net core – Advanced solutions built on C# with .NET Core for modern, cross-platform applications 👨‍💻 BACKEND Development Python: Expert in Python for server-side development Frameworks: Proficient in Django and Flask for building web applications Databases: Skilled in SQL, PostgreSQL, MySQL, and MongoDB for efficient data management Architecture: Experienced in applying MVC patterns for scalable applications APIs: Capable of integrating external services through REST and GraphQL 👨‍💻 FRONT END Development Proficient in HTML5, CSS responsive, JavaScript Experienced in React.js, Angular, Vue.js, react native, ionic, xamarin developer Responsive, cross-browser, ui/ux designer, ux/ui dashboard, ui ux designer app 👨‍💻AI TOOLS OpenAI API, DeepFace, ML/DL frameworks (TensorFlow, Keras, PyTorch, Scikit-learn), LangChain, Mistral, AgenticAI, Transformers RAG + custom AI tools: Document recognition and processing, Market Grabber, project management bots, AI for telephony, video/audio analysis Mobile App Development Native Mobile Development: Android, Kotlin, Java, iOS, Swift, KMP, KMM. Cross-Platform/Hybrid App Development: Flutter, Swift, Objective C, React Native, Xamarin, MAUI. General Expertise Website & Full Stack Development: Full stack development with ai .net full stack developer, .net software engineer, .net programmer, full stack developer, ai python full stack developer django, full stack web developer, full stack development, cms developer DevOps/DevSecOps: AWS, Azure, Docker, Kubernetes, GitLab-CI, Ansible, Terraform, etc Cross-platform app building with three.js, web application design, webflow web designer, website builders Integration tools: Data integration, websockets, ABP Framework, discord, Autotask Experienced in .net core web api, fullstack .net developer roles, with strong skills as a .net specialist. Skilled angular .net react developer, java developer with solid c sharp expertise. Worked on kogito for business automation, delivered ui ux-focused solutions. As an azure data engineer, handled scalable data pipelines. rust developer, python projects include backend developer tasks. Built app as a xamarin and web developer using java and javascript. Skilled in postgresql and web scrapping. Maintained legacy systems with .net webform. Collaborated with nft marketers, managed nft collab manage tasks. Full stack with react nodejs, modern react, including react typescript, react native developer roles. Acted as product owner in agile teams. Cloud deployments done on azure. Built interactive UIs using blazor. Why Choose us Microsoft certified talented developers and senior .net developer team High QA standards, including qa engineer roles Modern solutions: NFT programmer, metaverse, Microsoft .net, windows 10, Power Apps developer, SharePoint, market grabber Scalable team: full stack software developer, front end programmer, ios developer, ui ux designer Industries Banking, Trading, Cryptocurrency, Asset Management, Lending, Retail, Real Estate & Property Management, Food Delivery, Entertainment, Hospitality, Construction, Sports & Fitness, Travel & Tourism, Wellness, Medical Dashboard, Marketplace, E-commerce, Automotive, Human Resources, Education, E-learning, AI Assistants Seek new projects to put our .net ai, bring value to individuals, startups, companies.

🏆 𝗧𝗢𝗣 𝗥𝗔𝗧𝗘𝗗 𝗣𝗟𝗨𝗦 🏆 ✅ Mobile App Developer 7+ years of experience ✅ SaaS Mobile App Developer 5+ years ✅ 35 mobile app development jobs completed successfully ✅ Android and iOS Mobile Expert ✅ Built 27+ UX-first Mobile App development jobs for 22 companies ✅ On-Time and Cost-Effective Delivery ✅ Future-Proof Solutions Showing a Minimum 41% ROI ✅ 4354 mobile app development hours on Upwork and still counting ✅ 100% Job Success in mobile app development (Client Satisfaction Ratio) ✅ 98% of Clients Recommended working with me ✅ 80% Long-term Repeat Clients ✅ 7+ years of experience in mobile app development, 6 years experience in iOS mobile app development, 7 years experience in Swift and Kotlin, 4 years experience in Flutter, React Native, 2 years experience in KMM, KMP Full stack mobile app developer and mobile app UI UX designer with 7+ years of experience in Mobile App Development, specializing in iOS, Swift, Android, Kotlin, KMM, Kotlin Mutliplatform / KMP, React Native, and Flutter. I have successfully delivered 120+ mobile applications in different roles as mobile app developer, flutter app developer, flutter full stack developer, flutter flow, mobile app design, mobile ui ux designer, swift ios developer, android developer, kotlin developer, react native developer, mobile game developer achieving a 5-star rating on Upwork and helping clients scale their businesses with high-performance solutions. Apart from mobile app development, I specialize in Mobile App Design for both iOS and Android, as well as Web App Design for SaaS platforms. My expertise extends to Interaction Design, User Flow Design, and creating seamless User Experience (UX Design) and User Interface (UI Design). I follow a Design Thinking approach, ensuring every solution is user-centered and problem-solving. My process includes UI/UX Wireframing, Prototyping, and building Style Guides or UI-kits for consistent branding. I perform Design Audits and Design QA to maintain high standards across all projects. 🛠️ Design Tools: My designs come to life through powerful tools like Figma, Zeplin, and InVision for prototyping and collaboration. I leverage Adobe Illustrator, Adobe Photoshop, and Adobe XD for detailed visual design. For complex wireframes and flow mapping, I turn to Axure, Sketch, and Balsamiq. I also use Miro and Abstract for brainstorming and version control, while project communication and management happen in Slack and Jira. Our Expertise at a Glance • Mobile App Development: Android, iOS, & Cross-Platform App Development using Java, Kotlin, Swift, Objective C, Flutter, and more. • Website and Full Stack Development: Crafting seamless back-end experiences with .Net, Python, Java, Javascript, React.js, Angular.js, Node.js, MERN, MongoDB, PHP, etc. • Logo & UI/UX Design: Bringing your ideas to life with Adobe XD, Photoshop, Sketch, Figma, etc. • End-to-End Solutions: From logo design, UI/UX development, workflow setup, testing to deployment in app stores, we've got it all covered. We do not use v0.dev lovable.app CursorAI, Cursor, Windsurf, Trae, GitHub Copilot, Tabnine, Qodo, Devin AI, and AutoDev for speed up coding, we know other methods to do it efficiently. We offer a comprehensive range of development services across mobile, web, and cloud platforms. Our mobile app development expertise includes building Android and iOS applications using technologies such as Flutter, Swift, Objective-C, React Native, and Xamarin, optimized for both smartphones and tablets with a focus on cross-platform compatibility. In website and full stack development, we work with .NET technologies, including full stack .NET development, .NET Core, and Python with Django. Our team is experienced in developing both backend systems and user-friendly, responsive web interfaces, as well as working with various CMS platforms. Our DevOps and DevSecOps capabilities cover cloud infrastructure and automation, leveraging tools like AWS, Azure, Docker, Kubernetes, GitLab CI, Ansible, and Terraform to build secure and scalable deployment environments. We also build cross-platform and web applications using frameworks like Three.js and design tools such as Webflow, creating visually engaging and functional user experiences across devices. Additionally, we are well-versed in integration and automation tools, including WebSockets, data integration, the ABP Framework, Discord API, and Autotask, allowing us to create seamless connectivity and workflow automation between systems. Talent Good Knowledge, Talented, Experienced, Skilled, Strong Experience, Proven Experience, Agency, Team, Company, Specialist, Proven Track Record, Strong Background, Write Clean Code, Deep Expertise, Bring to Life, Cross-platform, Attention to Detail, Long Term. ⚡️ AVAILABLE FOR NEW PROJECTS ⚠️ Press Invite Button on my page and let's talk.

Mobile Flutter Developer with DevOps expertise — building cross-platform iOS & Android apps and owning the full delivery pipeline: AWS, Kubernetes, Ansible, Terraform, CI/CD. 10+ years in software engineering. I deliver production-ready Flutter apps together with the infrastructure that builds, deploys, and runs them. Flutter Development: Flutter & Dart — performance optimization, clean architecture, responsive UI/UX State management — BLoC, Provider, MobX, Riverpod Animations & graphics — custom animations, CustomPainter, Rive/Lottie, shaders Maps & geolocation — Google Maps, Mapbox, real-time tracking Native integrations — platform channels, C++ libraries, real-time audio processing App Store & Google Play deployment, release management DevOps & Cloud Infrastructure: Infrastructure as Code — Terraform, Ansible; Kubernetes orchestration with Helm CI/CD — automated builds, testing, and deployments (GitHub Actions, Jenkins, GitLab CI, Fastlane, Docker), including mobile release pipelines to App Store and Google Play Monitoring & observability — Prometheus, Grafana Cloud platforms — AWS, Google Cloud (GCP), Hetzner; Linux server administration Firebase & Supabase — auth, real-time database, cloud functions, hosting Backend Development: Node.js, Python, Java, Dart backends API design — REST, GraphQL, gRPC, WebSockets Databases — PostgreSQL, MySQL, MongoDB, Redis, SQLite AI & LLM: AI/LLM integrations in production apps — OpenAI, Anthropic (Claude), Gemini APIs AI-assisted development workflow — Claude Code and OpenAI Codex Experience: multiple production apps delivered end-to-end as a solo developer — UI, backend, cloud infrastructure, and deployment automation. Comfortable owning a product fully or working inside an experienced team. I care about code quality, long-term maintainability, and delivering real value — not just completing tasks. If you need someone who understands mobile development, backend, and the infrastructure that connects them into a working product — I'd be glad to help. = = = Career Highlights = = = Oct 2024 – Present — Senior Flutter & DevOps Engineer Building production Flutter apps end-to-end with cloud infrastructure and deployment automation: AI/LLM-powered features, real-time systems, infrastructure as code. Working independently, owning products from UI to deployment. Stack: Flutter/Dart, Python, AWS & Google Cloud, Kubernetes, Terraform, Ansible, Docker, Firebase, Supabase, PostgreSQL, MySQL, Redis, MongoDB Dec 2018 – Oct 2024 — Senior Flutter Developer Six+ years of Flutter in production since its early releases: multiple apps shipped to App Store and Google Play, real-time and data-driven architectures, solo ownership from UI to backend. Stack: Flutter/Dart, Supabase, Google Cloud, Firebase, PostgreSQL, SQLite, Linux 2015 – 2018 — Full-Stack JavaScript Developer Web applications and data visualization for production use. Stack: JavaScript (React, D3), Node.js, Python/Django, MongoDB 2010 – 2013 — Java Developer Enterprise web applications. Earned Oracle Certified Professional, Java Programmer. Stack: Java, GWT, Oracle DB 2006 – 2008 — Web Developer First commercial projects; Linux as a daily driver since then. Stack: PHP, JavaScript, MySQL, Linux = = = Technologies = = = Flutter • Dart • BLoC • Provider • Riverpod • MobX • CustomPainter • Rive • Lottie • Google Maps • Mapbox • Push Notifications • Firebase Cloud Messaging • In-App Purchases • Hive • CI/CD pipeline • GitHub Actions • Jenkins • GitLab CI • Fastlane • Docker • Kubernetes • Helm • Terraform • CloudFormation • Ansible • Prometheus • Grafana • Bash scripting • AWS • EC2 • S3 • EKS • Lambda • Google Cloud • GCP • Firebase • Supabase • Linux • Node.js • Python • Django • PostgreSQL • MySQL • MongoDB • Redis • REST API • GraphQL • gRPC • WebSockets • LLM integration • RAG • AI chatbot • OpenAI API • Anthropic API • Claude API • Gemini API • Claude Code • OpenAI Codex • Stripe • App Store • Google Play

I am a Senior Software Engineer with over 6 years of experience specializing in building scalable, fault-tolerant, and high-performance distributed systems. My expertise lies in architecting backend ecosystems from scratch and optimizing complex infrastructures for millions of users. I focus on decoupling business logic from infrastructure to create "future-proof" architectures. Whether it’s implementing gRPC for high-concurrency processing or designing event-driven architectures with RabbitMQ and Kafka, I ensure your system is both performant and maintainable. Core Technical Expertise: Languages: Go (Golang), Node.js, Python, TypeScript, Solidity. Communication & Protocols: gRPC, WebSockets, REST, GraphQL, SNS/SQS, Azure Service Bus. Architecture: Microservices, Event-Driven (EDA), Hexagonal Architecture, DDD. High-Load & Databases: PostgreSQL (Advanced Indexing/Schema Design), MongoDB, Redis, DynamoDB. Cloud & DevOps: AWS, Azure, Kubernetes (K8s), Docker, Prometheus, Grafana. Proven Business Impact: Performance at Scale: Designed and architected backends capable of processing 1,000,000+ RPS using Go and gRPC. Cost Optimization: Reduced monthly operational overhead by $20,000 through automated self-healing and auto-scaling systems. Reliability: Achieved 99.9% uptime during peak traffic by implementing robust payment engines and message brokers. AI & RAG: Slashed R&D costs by 30% by implementing optimized AI token usage via advanced RAG architectures. Monitoring & Incident Prevention: I don’t just write code; I ensure it stays up. I have extensive experience in production monitoring using Sentry, Prometheus, and Grafana to detect and resolve issues before they impact users. If you are looking for an engineer who can lead technical architecture from inception to production at scale, let’s connect.

We Can help you: ★ Product Design & Development 🔸 Create the architecture of your next mobile app using React Native and Flutter 🔸 A to Z app design and development 🔸 Set up a development team and delivery processes 🔸 Review the quality of the code 🔸 Help to find bottlenecks on the technologies side for the rapid growth of your product 🔸 Consultancy to make app GDPR, HIPAA, and MDR compliant ★ Software testing 🔸 QA Audits and Assessments 🔸 QA Staffing 🔸 Dedicated QA team 🔸 Managed testing 🔸 Mobile app testing 🔸 Web app testing 🔸 DevOps Hi 👋 my name is Liudmyla Dziubynska, and I am a professional software engineer with more than 8+ years of experience creating custom high-load platforms and applications. Since 2017, I have been leading a team of software development engineers with deep expertise and focusing on developing custom cross-platform and web applications using: 🔹 Javascript & TypeScript 🔹 ReactJS 🔹 React Native 🔹 Flutter 🔹 NodeJS (NestJS, Express) Our developers not only pay attention to technical aspects, but we also have experiences in business domains, such as: 🔸 HealthCare 🔸 FinTech 🔸 Logistics 🔸 SaaS solutions 📌 What value we can bring: • Technical risk management. We care about the technical edge cases of the product to avoid any data breaches or fines in the future • Direct communication with the whole team and transparent cooperation • Solid processes in development, testing, and product delivery • Flexible working with the various time zones 📌 Key information about ZenBit Tech: • Delivery software development services since 2017 • ISO13486 certified • Headquarters and R&D in Eastern Europe with the sales office in the UK • Participating in and committed to the IT community (IT hubs, organizing local events, meetings, etc.) 🤔 Interesting in building a scalable and successful product? I would be happy to share my experience and provide you with a solution!