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👋 Hello! Senior Java Developer, Team Lead & Architect with 10+ years of hands-on experience with 10+ years of hands-on experience building scalable, high-load web and mobile applications. I mainly work with Java backend, JavaScript, TypeScript, Oracle, Postgres databases. My core backend work is centered on Spring Boot, focusing on API development and production-grade RESTful services backed by PostgreSQL. My focus is on backend software architecture, ensuring scalability, clean boundaries, and long-term maintainability. ✔️ Ready-to-Use Integrations I can accelerate your product using proven, production-ready integrations: 🚀 AI & LLMs: ChatGPT, LLaMA, Mistral (text, images, vision, automation) 🚀 Payments: Stripe (card payments & transfers) 🚀 Voice & Media: ElevenLabs (speech & voice AI) 🚀 Communication: Zoom (voice & video integrations) My Specialization: ✅ Backend & Architecture: Java (10+ years): modern Java (Lambdas, Streams, Date/Time API), Spring (9+ years): Spring Boot, Spring Data, Spring Cloud for microservices and distributed systems, and Java EE: REST APIs, SOAP, JPA, third-party integrations ✅ Security & Frameworks: Keycloak with OAuth2 and JWT-based authentication, JHipster, Swagger, Liquibase, Axon, Vaadin, ORM: Hibernate, Blaze-Persistence ✅ Databases & Messaging: SQL (10+ years): PostgreSQL, MySQL, MariaDB, Oracle, NoSQL: MongoDB, Redis, Hazelcast, Messaging: Kafka, ActiveMQ, RabbitMQ, Zookeeper, Firebase Messaging ✅ DevOps & Observability: CI/CD: Jenkins, Docker, Kubernetes, ELK Stack (Logstash, Elasticsearch, Kibana) ✅ Quality & Delivery: Testing: JUnit, Mockito, Spring Test, Unit & Integration testing, Full SDLC, code reviews, refactoring, clean architecture 💡 Let’s discuss how I can help you build a reliable, scalable solution!

🚀 AVAILABLE FOR JAVA / SPRING BOOT | AWS CLOUD ENGAGEMENTS With over 8 years building backend systems as a Senior Java Developer, I solve complex technical challenges across the full stack from microservices to cloud-native infrastructure. Whether it's designing Spring Boot services, architecting AWS environments, or setting up DevOps pipelines, I bring the expertise that every Java Developer must have, combined with the cloud and infrastructure skills that modern systems demand. 𝗣𝗿𝗼𝗳𝗲𝘀𝘀𝗶𝗼𝗻𝗮𝗹 𝗕𝗮𝗰𝗸𝗴𝗿𝗼𝘂𝗻𝗱: ➡ Over 8 years as a Java Developer in end-to-end software development across the full delivery cycle. ➡ Designing Spring Boot microservices and high-performance Java applications for fintech, healthcare, SaaS, and e-commerce as a Java Backend Develope and now extending that into cloud engineering and DevOps. ➡ AWS Cloud Engineer - EC2, S3, Lambda, SQS, SNS, IAM, API Gateway, CloudFormation. I design and run cloud infrastructure, not just deploy to it. ➡ DevOps & CI/CD - Docker, Kubernetes (K8s), Helm, Terraform, Jenkins, Azure DevOps, OpenShift. Working with both AWS DevOps and Azure DevOps pipelines that ship code reliably. ➡ Network engineering in cloud environments 𝗟𝗲𝗮𝗱𝗲𝗿𝘀𝗵𝗶𝗽 𝗮𝗻𝗱 𝗙𝗼𝗰𝘂𝘀: ➡ Led cross-functional teams as a Senior Java Developer, delivering clean architecture and scalable cloud-connected solutions. ➡ Guided developers in Spring Boot, Java, and React as a lead Java Backend Developer, maintaining enterprise-grade quality standards. ➡ Consistently raised team output by implementing the best practices any Senior Java Developer is expected to own. 𝐏𝐫𝐨𝐠𝐫𝐚𝐦𝐦𝐢𝐧𝐠 𝐋𝐚𝐧𝐠𝐮𝐚𝐠𝐞𝐬 & 𝐅𝐫𝐚𝐦𝐞𝐰𝐨𝐫𝐤𝐬 As a Java Backend Developer I work with: ✅ Languages: Java, Java 8, Java 11, Java SE, Java EE, JavaFX, SQL, JSON, XML, YAML, Python ✅ Frameworks: Spring (Spring Boot, Spring MVC, Spring Data, Spring Cloud, Spring Security, Spring AOP, Spring Batch, Spring WebFlux), Hibernate, JPA, Quarkus, React, Node.js As a Senior Java Developer, I use these to build enterprise applications that are maintainable, scalable, and secure. 𝐂𝐥𝐨𝐮𝐝, 𝐃𝐞𝐯𝐎𝐩𝐬 & 𝐈𝐧𝐟𝐫𝐚𝐬𝐭𝐫𝐮𝐜𝐭𝐮𝐫𝐞 ✅ AWS Cloud Engineer: EC2, S3, SQS, SNS, Lambda, IAM, RDS, API Gateway, CloudWatch, CloudFormation ✅ Azure Cloud Engineer: Azure DevOps, Azure Kubernetes Service ✅ Google Cloud Engineer: GCP core services ✅ Kubernetes, Helm, Docker, Terraform, Jenkins, Maven, Gradle, Git (GitLab, Bitbucket) ✅ AWS DevOps & Azure DevOps pipelines, OpenShift, Infrastructure as Code 𝐃𝐚𝐭𝐚𝐛𝐚𝐬𝐞𝐬 & 𝐌𝐞𝐬𝐬𝐚𝐠𝐢𝐧𝐠 ✅ MySQL, PostgreSQL, MongoDB, Redis, DynamoDB ✅ Kafka, RabbitMQ, REST APIs, SOAP, gRPC, WebSockets 𝐀𝐫𝐜𝐡𝐢𝐭𝐞𝐜𝐭𝐮𝐫𝐚𝐥 𝐏𝐚𝐭𝐭𝐞𝐫𝐧𝐬 & 𝐏𝐫𝐢𝐧𝐜𝐢𝐩𝐥𝐞𝐬 ✅ Architectures: Microservices, Event-driven, SOA, Monoliths ✅ Patterns: CQRS, Saga, Circuit Breakers, Service Discovery, Distributed Systems ✅ Principles: SOLID, Clean Code, Domain-Driven Design (DDD) A Java Developer must master these to deliver systems that scale that's what I build every day. 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭 𝐏𝐫𝐚𝐜𝐭𝐢𝐜𝐞𝐬 ✅ Testing: JUnit, Mockito, TestNG, Unit & Integration Testing ✅ Methodologies: Agile (Scrum, Kanban), TDD, BDD ✅ Version Control: Git, GitLab, Bitbucket My workflow as a Senior Java Developer runs on Agile principles and a test-first mindset, producing applications that are production-ready from day one. 𝐀𝐫𝐞𝐚𝐬 𝐨𝐟 𝐀𝐜𝐭𝐢𝐯𝐢𝐭𝐲 Backend development • Full-stack development with Spring Boot + React • AWS cloud engineering • Azure cloud engineering • Google cloud engineering • DevOps & CI/CD • Network engineering • API integration • Cloud-native applications • SaaS platforms • Android Java development As a Senior Java Developer and aws cloud engineer, I cover the full path from backend code to cloud deployment. 𝐈𝐧𝐝𝐮𝐬𝐭𝐫𝐢𝐞𝐬 During my career as a Java Backend Developer I've worked across: Fintech • Healthcare • E-commerce • Enterprise Applications • Cloud Computing • Telecommunications • Logistics • Travel & Hospitality • Media • Automotive • Blockchain • IoT • SaaS • Retail 𝐒𝐩𝐞𝐜𝐢𝐚𝐥𝐢𝐳𝐚𝐭𝐢𝐨𝐧𝐬 & 𝐑𝐨𝐥𝐞𝐬 ✔ Senior Java Developer ✔ Java Spring Boot Developer ✔ Java Backend Developer ✔ AWS Cloud Engineer / AWS DevOps Engineer ✔ Azure Cloud Engineer / Azure DevOps ✔ Google Cloud Engineer ✔ Kubernetes & Network Engineer ✔ API Developer ✔ Full-Stack Developer (Spring Boot + React) ✔ Android Java App Developer 𝐒𝐞𝐫𝐯𝐢𝐜𝐞𝐬 ✔ Java Development Services ✔ Spring Boot Microservices Development ✔ AWS Cloud Engineering & Migration ✔ AWS DevOps / Azure DevOps Pipeline Setup ✔ Kubernetes Cluster Management ✔ Infrastructure as Code (Terraform) ✔ API & System Integration ✔ SaaS Application Development ✔ Android Java App Development ✔ Performance Tuning & Code Reviews 👉 Need a Java Developer who writes clean code and ships it to the cloud? Just drop me a message

⭐⭐⭐⭐⭐"Mykyta has exceptional characteristics both in hard and soft skills. He took a part in complex software development projects as a part of a large mixed group. The feedback from our customers and team is always positive." ⭐I'm the highest-rated and highest-earning Java & Groovy freelancer on Upwork with numerous 5-star reviews, including overly positive feedback. ⭐ I've developed different custom specific software using modern java & groovy software using microservice and monolithic architecture, improved performance, refactored and tested in next business domains: ✅ Utilities ✅ Fintech ✅ Auto ✅ Security ✅ Cryptocurrency ✅✅✅ Brief information about me! ✅✅✅ ✅ Senior Java & Groovy Software Engineer ✅ Specializing in back-end development | Cloud Integrations (AWS, GCP, Azure) ✅ I have over 6.5+ years of experience in Java development ✅ Experienced both in developing software from scratch and maintaining large existing projects ✅ I have hands-on experience in developing back-end web services with micro-service or monolith architecture using Java technology stack, including modern cloud-based solutions. 🌟 WHY YOU SHOULD CHOOSE ME OVER OTHERS? 🌟 ✅ Clients' feedback: I am concentrating on giving VALUE and bringing SUCCESS to all of my customers, earning their TRUST and helping them to EARN MONEY. ALL customers' feedback on my Profile is extremely important to me and proves the value that I provide. ✅ Responsiveness: Communication is extremely important as a part of every business ever existed, and once it is fast and clear, it may lead to awesome results, that's why I tend to be available for my customers in no time, reply fast and clear, as well as I try to be fair, understanding and responsive. ✅ Kindness and Empathy: My main personal principles that I implement in every facet of my life. Treating everyone with respect, aiming to understand the whole situation or problem to solve the pain of my client, and constantly work to IMPROVE the client's product. 🙋🏼‍♂️I am eager to work with you, to provide high-quality code, reliable, consistent solutions, solve your problems and bring success to your business. Contact me, and we will discuss how we can work together to FULLY meet your Business Needs, follow your business rules, and bring you success. A big area of expertise: - REST API design and development - Horizontally scalable and highly available systems - Automating development workflows and deployment pipelines - Micro-service design and development - Design and development of decentralized applications (DApps) - Monitoring, log aggregation - Java and Groovy development - Service-Oriented architecture - Spring Framework (including cloud-based stack) - Experience in NoSQL Development (MongoDB, Neo4j) - Performance and Scalability Optimization Huge Skills & Technologies set: - Java/Groovy - AWS - Linux (with distributives) - Jenkins, CircleCI, Rundeck, Rancher - Docker - MySQL, Postgres - Redis, MongoDB, Neo4j. - RabbitMQ, ActiveMQ, SQS, RabbitMQ

Senior Backend Java Engineer and AI Developer with 7+ years of production experience, 8,800+ hours on Upwork, $300K+ earned, and a 100% Job Success Score (Top Rated Plus). I build web platforms, backend systems, and AI integrations — my own delivery is Python-first (LLM-powered agents, RAG pipelines, distributed REST APIs, data extraction systems, and cloud-native infrastructure on AWS), and for Java or Spring Boot engagements I lead, my engineering team brings deep Spring Boot, microservices, AWS architecture, and Auth0/OAuth 2.0 identity experience to the JVM side. Every engagement ends with a system that runs in production — properly architected, monitored, and ready to grow with the business. Technical stack that I can provide for your project: ☕ Java & Spring Boot Engineering (team-backed): Spring Boot microservices and REST/GraphQL/gRPC services, Java 21 upgrades, and Play Framework → Spring Boot migrations. Auth0-based identity with multiple OAuth 2.0 grant types (Authorization Code, Device, Password, Passwordless), SSO, JWT, and biometric authentication across 15+ international markets. Full AWS backend architectures provisioned from scratch via Terraform (API Gateway, ECS, Lambda, RDS, DynamoDB, S3, CloudFront, Route 53, IAM, SQS, SNS, EventBridge, CloudWatch), CI/CD with GitLab, Jenkins (Groovy), and BitBucket Pipelines, Hibernate, JPA, JUnit, Mockito, Testcontainers, Maven, Gradle, SonarQube, Veracode. 🤖 AI & LLM Development: I build LLM agents with multi-turn state using LangChain and LangGraph — the kind that run in production on Telegram, Discord, and WhatsApp. For knowledge retrieval I work with RAG pipelines backed by Qdrant and LLaMA-Index, with real semantic search over internal documents. Prompt engineering is a proper workflow here — evaluation frameworks, LangSmith observability, structured output validation. I integrate agentic workflows through API (OpenAI, Claude, Anthropic, Gemini) with full output control. ☁️ Cloud & Infrastructure: I work with the full AWS stack in production — S3, SQS, Lambda, Athena, DynamoDB, EKS, Kinesis, Bedrock, CloudFront, also Docker, Kubernetes (Helm + ArgoCD), and Terraform for reproducible infrastructure as code. Observability built in Datadog APM, OpenTelemetry, Sentry, and vector database management with Qdrant and AWS OpenSearch for semantic search and RAG retrieval. 🧭 When you choose me, you get a clear roadmap: - Consultation — I start by understanding your request, goals, and constraints before we start - Honest scoping — based on your needs I give you a real estimate with clear timelines - Full transparency — Agile workflow, regular meetings, and open communication at every step of the process - Clean delivery — proper documentation and handoff, so you truly own what I build - Support from idea to launch — I stay in contact after delivery, and stay involved as long as you needed 📩 Ready to get started? Contact me — I respond fast. Buzz words: Java JavaScript Python PHP API Web Development Node.js Android API Integration React Android App Development HTML MySQL Mobile App Development Amazon Web Services RESTful API Artificial Intelligence Web Application HTML5 CSS Spring Boot C++ iOS C# Smartphone Machine Learning AI Agent Development AI Development PostgreSQL AI App Development Data Scraping Data Science Automation Deep Learning AI Model Integration TensorFlow Django Natural Language Processing Claude Chatbot Development API Development TypeScript n8n OpenAI API AI Bot Full-Stack Development FastAPI Docker Next.js LLM Prompt Engineering Data Mining Computer Vision SaaS LangChain Software Architecture & Design Data Extraction Database Architecture SQL Lead Generation Vector Database Web Scraping Java Spring Boot Spring Framework Microservices Cloud Architect Terraform Apache Kafka Auth0 OAuth 2.0 JWT SSO Hibernate JPA JUnit Mockito Testcontainers Maven Gradle GitLab CI/CD Jenkins BitBucket Pipelines Stripe API GraphQL gRPC Java 21 AWS Lambda AWS ECS AWS API Gateway Web Platform Backend Architecture AI Integration

📢 Available for new projects 📢 I'm a Senior Java Developer with more than 10 years of commercial experience building stable, scalable, and secure backend systems. I specialize in Spring Boot microservices and cloud-native architecture — and I've shipped production systems in Fintech, EdTech, Healthcare, Retail, Hospitality, etc. My core strength is backend architecture: clean APIs, event-driven systems, and services that scale. I also work across the full stack development when needed — React on the frontend, Node.js for integrations, and AWS for deployment and infrastructure. What I bring to your project: - Production-grade Spring Boot microservices and REST APIs - Cloud infrastructure on AWS with Docker and CI/CD pipelines - Full-stack capability: Java backend + React frontend - Relational and NoSQL databases: PostgreSQL, MySQL, MongoDB - Clean, maintainable code with TDD and Agile workflows I've worked on SaaS platforms, enterprise systems, and MVPs — from initial architecture through to deployment. Go-To Stack: Java (Spring Boot, Spring Cloud, Hibernate) · React · Node.js · AWS · Docker · PostgreSQL · MongoDB · Jenkins · GitFlow Ready to start - just drop me a message and we will start working!

Greetings! I have been working as a Java developer for more than 14 years, my main clients are from Europe, Israel, India, China and USA. I am developing both desktop software and web applications, RESTful microservices etc. You can safely entrust me with the work on your project and will never be disappointed in our cooperation, I can guarantee the high responsibility and quality of the tasks that I carry out, which you can be sure of when you take me to your team. Main skills: Java technologies: - Java 8, 9, 11, 17 - JavaFX - Zuul, Ribbon, Eureka - Spring: Core, MVC, Web-flow, Integration, Batch, Boot, Social, Data, Config - Quarkus - Maven 2/3, JUnit 4 - JMS: RabbitMQ, ActiveMQ - JDBC, Hibernate 3.x, Neo4j - ESB, JNDI, JSP - WebDriver - JHipster NodeJS development: assisting libraries: express, async, soap, log4js connectivity: mongodb, redis, stomp-client, socket-io testing, building: should, mocha, grunt deployment: PM2, npm publishing and related activities promises, some EcmaScript 6 thingies Front-end development: Angular HTML 5, CSS 3, JavaScript (ES 5/6) JQuery, Bootstrap Other: pug (jade) Datastores: MySQL, MongoDB, PostgreSQL Other: AWS, Google Cloud, Azure services: Compute Engine, Cloud Storage, Data Store, SQL regular usage of Linux-based systems (anything necessary to develop and support software) infrastructure: Jenkins, SVN, git - commit/push/pull level ActiveMQ, Camel Elasticsearch