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👋 Hi, I'm Julia - your reliable tech partner ✅ 9+ years in software development ✅ 41+ jobs on UpWork ✅ 155+ web and mobile projects delivered ✅ 20,500+ Upwork hours in React / Next.js / Node.js / React Native ✅ 75% repeat clients - partnerships lasting 6-18+ months ✅ 40+ MVPs released, 5-8 weeks from MVP to pilot launch ✅ 35+ in-house engineers, matching in 24 hours or less ✅ 2-week trial period - you risk nothing ✅ Products we support include platforms with 5M+ daily users My team helps companies hire in-house, CTO-approved engineers who join fast, take ownership, and deliver production-ready software. My goal: save up to 40% of your budget and still get a market-ready, stable, scalable product. Why teams choose us: 🔹 In-house, not freelance-marketplace roulette. Every engineer is personally screened and approved by our CTO before joining your project. 🔹 Speed without chaos. Engineer matched within 24h, weekly demos, code review and QA on every delivery. 🔹 Ownership. Our engineers don't wait for tickets - they flag risks, suggest architecture improvements, and drive the product forward. 📌 How we work: Discovery & technical planning → engineer matching within 24h → 2-week trial → weekly demos and reports → CTO-approved delivery with code review and QA → long-term support after launch. 🚀 React / Next.js / Full Stack We build SaaS platforms, marketplaces, dashboards, admin panels, CRMs, and scalable web apps as react developer, react js developer, nextjs developer, next js developer, web app developer react, full stack developer react node, and full stack developer supabase react. Stack: React, Next.js, Node.js, TypeScript, Supabase, PostgreSQL, Firebase, MongoDB, REST API, GraphQL, Stripe, OAuth, WebSockets, AWS, Vercel, Docker. MVP development, legacy code takeover, architecture modernization, Core Web Vitals, API integrations, payments, auth, subscriptions, user roles, production launch. A strong fit if you need a react developer, frontend developer react, web developer, full stack developer, mern developer, or backend engineer. 📱 React Native / Mobile iOS and Android apps as react native developer, react native developer expo, react native app developer, mobile app developer. React Native, Expo, Firebase, Supabase, Node.js, API-driven architecture. App takeover, maintenance, push notifications, App Store / Google Play releases, payments, backend integrations. Mixed environments: flutter developer, android developer. 🤖 AI SaaS / AI Development 25+ AI products and features shipped: AI SaaS, AI MVP, AI chatbot development, AI agent development, RAG chatbot, copilots. Stack: OpenAI API, Claude API, LLMs, RAG, prompt engineering, Generative AI, Python, FastAPI, pgvector, web scraping, automation, AI workflow validation. 🧩 Mixed-Stack Support Core focus: React, Next.js, Node.js, React Native, TypeScript, Supabase, AI. We also support wordpress, vue, angular, python developer, scala developer, and other web/mobile technologies. 🏆 Industries 📦 Logistics - 5+ projects: tracking, shipment dashboards, carrier/shipper workflows, maps 🏥 HealthTech - 4+ projects: medical booking, clinic platforms, patient flows 🛒 Marketplaces & E-commerce - 15+ projects: multi-vendor, Stripe, subscriptions, bidding, complex search 🏠 PropTech - 5+ projects: listings, booking flows, agent dashboards, rental platforms 🤖 AI Startups - 25+ products: chatbots, agents, copilots, OpenAI / Claude integrations 💰 FinTech - 3+ projects: Stripe Connect, billing, payment flows, invoicing 🎮 Gaming - 5+ projects, incl. 2 major global gaming brands: dashboards, analytics, real-time 📚 EdTech - 5+ projects: student dashboards, progress tracking, content platforms 📣 MarTech - 1 global market-leading project: analytics, segmentation, workflows ⚽ SportsTech - 10+ projects: live data, events, rankings, stats, mobile apps 🚀 Building a SaaS, MVP, marketplace, React app, Next.js platform, React Native app, or AI product? Click "Invite" or "Hire" - I'll help you clear the estimate or discovery phase within 24 hours or less.

❇️ Experienced Software Engineer (TS, Java, Scala) ❇️ Technical Leader ❇️ Expert in Enterprise Web Apps, Microservices, Serverless, Full-stack, Functional programming

I am a seasoned software developer with over 10 years of experience specializing in Backend and Full-Stack development. I pride myself on my excellent problem-solving skills and have a strong passion for writing clean and testable code. Clear communication is one of my strengths, making me a valuable team member in any software development project. Preferred Tech Stack: Backend: Java, Spring Boot, Thymeleaf, REST API, PostgreSQL, AWS, Linux, Tomcat, Nginx Frontend (Web): HTML, CSS, Sass, Javascript Frontend (Mobile): Flutter, Dart Cross-Platform: Flutter, Dart I am also proficient in the following technologies: Languages: Java, Scala, Groovy, Kotlin, Golang, JavaScript, TypeScript, Python, Dart, SQL Databases: PostgreSQL, MySQL, Oracle, Cassandra, MongoDB, SQLite, Neo4j Frameworks (Backend): Spring Boot, Spring Security, OpenAPI, Kafka, Zookeeper, Grails Frameworks (Frontend): Angular, React, Flutter, jQuery, Bootstrap Security: Spring Security, OAuth, JWT Technologies: HTML, CSS, JSON, XML, REST API API: REST API, OpenAPI, Swagger Messaging: Kafka, ActiveMQ, RabbitMQ Search: ElasticSearch, Lucene, Kibana Logging: ElasticSearch, Logstash, Kibana Cloud Providers: AWS, Google Cloud Testing: JUnit, Mockito, TestNG, Selenium, Cucumber, Katalon Studio Development Tools: Intellij IDEA, VSCode, Android Studio

👋 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!

I am a Senior Java Developer with 10+ years of experience in architecting and developing robust, high-load, and data-intensive backend systems. As an AWS Certified Solution Architect, I specialize in cloud-based solutions that ensure security, scalability, and peak performance. I also have a strong knowledge of software development lifecycle, testing practices, and approaches, especially in FinTech, EV Charging, Gambling, and AI/ML niches. 💡 What I Offer: ✔️ Expert in Java & Cloud-Based Development – I design and build high-performance backend solutions for web and mobile applications. ✔️ FinTech, EV Charging & AI/ML Specialist – I develop solutions tailored to banking, investment, digital wallets, insurance, and other high-tech industries. ✔️ High-Load & Scalable Architectures – Skilled in optimizing multi-component systems for speed, efficiency, and reliability. ✔️ Seamless Team Collaboration – Experienced in working with startups and enterprises across Europe, Asia, and South Africa 🔍 Industries I Excel In: 📈 FinTech & Banking – Digital wallets, dashboards, financial management tools, and investment platforms. ⚡ EV Charging & Energy – Backend solutions for OCPP, OCPI, OICP-integrated charging networks. 🎲 Gambling & AI/ML – AI-driven platforms and real-time data processing. 🟩 🟩 🟩 🟩 Tech Stack & Expertise 💻 Languages: Java, JavaScript 📚 Frameworks: Spring (MVC, Boot, IoC, Data, Kafka), Akka, Hibernate, ReactiveMongo, GraphQL, Vue.js ☁ Cloud & DevOps: AWS (SQS, SNS, Param Store), Docker, Jenkins 🛢 Databases: MySQL, MongoDB, PostgreSQL, MariaDB, SQL 🧪 Testing: Mockito, JUnit, ScalaTest 📡 Other: IntelliJ IDEA, SBT, Nats, Kafka (Mirror, Connectors, Clusters), Maven, Linux, REST, Scrum, Docker, HTML, CSS, Nuxt, Jenkins, OOP, OCPP, OICP, OCPI PORTFOLIO ✅ Banking application for one of the biggest banking groups in Africa. Environment: Java 8, Spring Boot, Maven, PostgreSQL, AWS (SQS, SNS, Param Store) ✅ Food delivery platform with multiple user roles for a Japanese customer. Environment: Java 8, Spring Boot, Maven, MongoDB, Kafka, PostgreSQL, AWS, Gitlab, Hibernate, SQL, Mongo, CircleCI ✅ Data aggregation system for Casino Gambling apps. Environment: Java 8, Spring Boot, Maven, MongoDB, Kafka ✅ EVCS management system with a back-office platform for a Belgian start-up. Environment: Java 11, Spring Boot, Maven, MongoDB, Kafka, MariaDB, AWS, Gitlab, Hibernate, SQL, OCPP, OCPI, OICP ✅ US EVCS management system with a back-office platform. Environment: Java 17, Java Reactive Programming, Spring Boot, Maven, MongoDB, Kafka, MySQL, AWS, Gitlab, Hibernate, SQL, OCPP ✅ EVCS management system for an underground parking company. Environment: Java 8, Spring Boot, Maven, MongoDB, Kafka, MySQL, AWS, Gitlab, Hibernate, SQL ✅ EVCS management and a back-office platform with a mobile app developed for clients’ access. Environment: Java 8, Spring Boot, Maven, MongoDB, Kafka, MySQL, AWS, Gitlab, Hibernate, SQL ✅ A mailing system for a Moroccan software company. Environment: Scala, Akka (Actor, Remote, Http, Stream), Spray, Mongo, ReactiveMongo, Mockito, ScalaTest, Colossus Framework (HTTP server), scalaJ, etc. I was a Lead Developer and Architect of these projects, working with the AWS services & Microservice architectures, and assisting the DevOps team. LANGUAGES I SPEAK Ukrainian is my native language. Besides, I have strong English skills. Most of my previous customers were English-speaking, so I am comfortable communicating in English. MY TEAM I am at ease as an individual contributor, but being a team player works best for me. So I joined Extrawest — an Upwork Top Rated Agency specializing in FinTech and Banking, Gambling and Betting, Food Ordering and Delivery, Logistics and Fleet Management, Medical Insurance and Healthcare, and EV Charging since 2006. Most of our resources are based in Europe, so we’ve been working with customers from over 20 countries (the US, Canada, Australia, most of the EU, South Africa, Singapore, and Japan). Hence, it won’t be a problem for us to adjust to your timezone and working schedule. INVITE ME FOR AN INTERVIEW If you are moving towards great goals and unique ideas, invite me for an interview, and let’s streamline your business’s growth together! 🟩 🟩 🟩 🟩 My Agency Skills: Front-End (Frontend) Development, Back-End (Backend) Development, Full-Stack (Fullstack) Development, Mobile Development, AI/ML, EV Charging, Automotive, Logistics, Delivery, Food Ordering, FinTech, Banking, Loan, Mortgage, Dashboard, Healthcare, Insurance, Betting, Gambling, Flutter, Dart, JavaScript (JS), TypeScript (TS), Angular, Vue.js (VueJS, Vue), React.js (ReactJS, React), Node.js (NodeJS, Node), Java, Spring, SpringBoot, Hibernate, Python, Django, Scrapy, Quality Assurance (QA), UI/UX Design, Figma, Adobe Creative Cloud, DevOps, Amazon Web Services (AWS), Google Cloud Platform (GCP), Project Management (PM).

Looking for an Apache Kafka and Java engineer who can design real-time streaming and data pipelines that hold up under production load? Over the past decade I have built Java backend, Apache Kafka streaming, and data-engineering pipelines across SoftServe, Eleks, and Euristiq, with the last six-plus years centered on Kafka, Kafka Streams, and Apache Flink for platforms that cannot afford to drop a message - including IoT telemetry ingestion at scale. ✅ Apache Kafka and Java engineer, 10 years backend, 6+ years on Kafka and streaming ✅ Two paid Upwork engagements closed at 5.0 of 5 - a Kafka Streams pipeline and an Apache Flink PoC ✅ 100% Job Success Score across 211 tracked hours, AWS Solutions Architect Associate certified ✅ Production Kafka, Kafka Streams, Kafka Connect, and Flink on Kubernetes, plus data-engineering and MQTT IoT ingestion pipelines ━━━━━━━━━━━━━━━━━━━━━━━━ 🔷 What I Do as Your Apache Kafka and Java Engineer I design and build streaming data pipelines and Java backend systems that scale independently of the write path and stay reliable when volume spikes. My work covers Apache Kafka topic and partition strategy, Kafka Streams stateful processing, Kafka Connect integrations, and Apache Flink stream processing, deployed on Kubernetes with monitoring in place. Whether you need a new Kafka pipeline, a data-engineering or ETL workload, a Spring Boot microservice backend, an event-driven architecture, or a Flink real-time processing layer, I bring production-grade engineering and clean handover to every project. 🔷 Core Apache Kafka and Java Backend Services ▸ Apache Kafka pipeline design - topic and partition strategy, consumer groups, delivery semantics ▸ Kafka Streams stateful processing, Kafka Connect source and sink connectors, schema registry ▸ Apache Flink real-time stream processing and fault-tolerant pipeline architecture ▸ Data engineering, ETL pipelines, and Big Data batch and streaming workloads ▸ MQTT-based IoT ingestion feeding Kafka topics downstream ▸ Java and Kotlin Spring Boot microservices, REST and GraphQL APIs ▸ Event-driven architecture and high-throughput backend services ▸ Elasticsearch search infrastructure downstream of Kafka topics ▸ Kubernetes and Docker deployment on AWS and GCP 🔷 Where I Have Shipped It At Euristiq, an AWS Advanced Tier partner, I build production data and backend systems for enterprise clients: moving service-to-service messaging onto Apache Kafka, building Kafka and Kubernetes backends for high-load platforms, and standing up MQTT IoT ingestion that feeds Kafka topics downstream. On Upwork, a Kafka Streams data transformation pipeline and an Apache Flink processing PoC both closed at 5.0 of 5 across more than 200 tracked hours, and the Kafka Streams client left a review citing strong technical skills, communication, and a will-hire-again. Earlier roles at Eleks and SoftServe covered Java and Spring Framework backend development, SQL design, and REST API engineering for global software teams. 🔷 Who I Work With I work best with teams that have a real data problem, not a tutorial one: product companies pushing high event volume, fintech and IoT platforms with hard reliability needs, and engineering teams who already know they need Apache Kafka or Apache Flink and want someone who has run them in production. If your pipeline only needs to move a few rows a day, I am probably overqualified for it. 🔷 My Engineering Process Send me your architecture and within 24 hours I will tell you whether the approach fits your scale, before any contract is signed. From there: a written design covering Kafka topic and partition strategy, consumer group layout, and delivery semantics; then implementation in Java or Kotlin on Kubernetes with monitoring; then a handover your own team can run. No black-box Kafka pipelines you cannot maintain after I leave. 🛠 Tech Stack ⚡ Apache Kafka, Kafka Streams, Kafka Connect, Apache Flink ⚡ Java, Kotlin, Spring Boot, Spring Framework ⚡ Kubernetes, Docker, AWS, GCP ⚡ Elasticsearch, MongoDB, SQL, GraphQL ⚡ MQTT, schema registry, ETL pipelines ━━━━━━━━━━━━━━━━━━━━━━━━ If you need an Apache Kafka and Java engineer who designs streaming systems that survive real load and hands them over clean, send me a message. Happy to review your current pipeline architecture or jump on a call to scope your project.