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I’m a Senior Web Developer, Team Lead, and Software Architect with over 20 years of experience building robust web applications across a wide range of industries and domains. Soft Skills • Leading and organizing agile development processes • Translating ideas into clear wireframes and product concepts • Designing scalable and efficient database architectures • Building and mentoring high-performing teams • Communicating effectively with non-technical stakeholders Technologies • Ruby on Rails • PostgreSQL, MySQL, Neo4j, Elasticsearch • JavaScript (Stimulus, Turbo.js, Vue.js) • Linux system administration, AWS, Heroku, Docker • HTML5, CSS, Tailwind If you have an idea for a project or need technical leadership, feel free to get in touch.

⭐⭐⭐⭐⭐ Top Rated Plus on Upwork 100% Job Success Score I'm a Java developer with 8+ years delivering production-grade systems from serverless AWS architectures to distributed microservices serving healthcare and fintech clients. 𝗪𝗵𝗮𝘁 𝗜'𝘃𝗲 𝗕𝘂𝗶𝗹𝘁 ➡ As lead Java developer at my current company, managed a team of 8 engineers over 7 years — delivering 4 production systems across healthcare, fintech, and AI verticals. ➡ Designed serverless AWS infrastructure for a US longevity and healthcare platform as an AWS developer — Lambda, AppSync, DynamoDB, Cognito, SNS/SQS, Stripe, HubSpot currently in production. ➡ Led migration from monolithic Spring apps to distributed microservices — reducing deployment complexity and enabling independent scaling per service. ➡ Built a PDF/UA accessibility compliance platform as backend developer using Java 21, iText 7, PDFBox, veraPDF processing and remediating documents of hundreds of pages against international accessibility standards. ➡ Delivered an AI-powered workflow automation platform as an AI developer integrating Spring AI, Azure cloud, and automated Stripe subscription workflows. ➡ Shipped a medical practitioner dashboard integrating 3rd-party hardware APIs and clinical toolkits as backend developer and tech lead serving real patients and practitioners in production. Core experience as a Java developer and Backend developer As a Java developer with 8+ years in production systems, my core is Java 8 through Java 21 with the full Spring ecosystem Boot, Cloud, Security, WebFlux, Batch, and Spring AI for AI-integrated backends. I work across both relational (PostgreSQL, MySQL) and NoSQL (MongoDB, DynamoDB, Redis) databases, selecting the right store based on access patterns not habit. As a backend developer I've optimised slow MongoDB queries to cut response times, redesigned DynamoDB access patterns for a high-throughput healthcare API, and built Redis caching layers that kept latency flat under load. As an AWS developer, my hands-on stack covers Lambda, AppSync, DynamoDB, Cognito, SQS, SNS, SES, S3, API Gateway, Route 53, and CloudFormation built and maintained in a live US healthcare platform. I design serverless pipelines end-to-end, not just deploy to them. For async workloads I wire event-driven systems using Kafka, RabbitMQ, or AWS SNS/SQS depending on durability and throughput requirements. On the container side: Docker, Kubernetes, Helm, OpenShift, Terraform, and Jenkins full IaC from infrastructure definition to CI/CD pipeline. As an AI developer, I've shipped Spring AI integrations for workflow automation backends, built document intelligence services capable of processing and remediating hundreds-of-pages PDFs against accessibility standards, and connected GraphQL APIs via AWS AppSync for mobile and web AI-driven applications. I also have production experience integrating medical hardware APIs, Stripe subscription billing, and HubSpot CRM sync into Java backends the kind of third-party integration work every backend developer eventually owns in a real product. AWS Developer & 𝗖𝗹𝗼𝘂𝗱 𝗘𝗻𝗴𝗶𝗻𝗲𝗲𝗿𝗶𝗻𝗴 ✅ Currently operating as AWS developer on a live healthcare platform Lambda, AppSync, DynamoDB, Cognito, SQS/SNS/SES, S3, API Gateway, Route 53, CloudFormation ✅ Experience as AWS developer across serverless, containerized (ECS/K8s), and IaC (Terraform, CloudFormation) environments ✅ Also experienced across Azure (AKS, Azure DevOps) and GCP as multi-cloud backend developer ✅ Kubernetes, Helm, Docker, OpenShift, Jenkins, Terraform the full DevOps chain every AWS developer deploys through AI developer 𝗖𝗮𝗽𝗮𝗯𝗶𝗹𝗶𝘁𝗶𝗲𝘀 ✅ Delivered AI-powered backend services as AI developer using Spring AI automated content generation and workflow orchestration at scale ✅ AWS AppSync + DynamoDB + Cognito pipeline for a live healthcare platform: the architecture an AI developer builds when latency and data integrity are non-negotiable ✅ Experienced AI developer integrating third-party AI tooling with enterprise Java backends designing event-driven pipelines that handle async AI workloads via Kafka and SQS ✅ As AI developer, built document intelligence features automated PDF tagging, structure remediation, and accessibility validation across large document corpora 𝗜𝗻𝗱𝘂𝘀𝘁𝗿𝗶𝗲𝘀 Healthcare · Fintech · SaaS · E-commerce · Logistics · Telecom · IoT · Blockchain · Automotive · Media 𝗦𝗽𝗲𝗰𝗶𝗮𝗹𝗶𝘇𝗮𝘁𝗶𝗼𝗻𝘀 & 𝗥𝗼𝗹𝗲𝘀 ✔ Senior Java Developer · Java Spring Boot Developer · Java Backend Developer ✔ AWS Cloud Engineer · AWS DevOps Engineer ✔ Azure Cloud Engineer · Google Cloud Engineer ✔ AI Backend Developer · Full-Stack Developer (Spring Boot + React) ✔ AI Backend Developer · Full-Stack Developer (Spring Boot + React) Need a Java developer, backend developer, AWS developer, or AI developer who ships production systems — not prototypes? Drop me a message. 04/06/2026

👋 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've been working with well known clients such as VMware, Avaya and Alcatel-Lucent. I specialize in building web applications using Ruby on Rails framework. In development, I focus on delivering value for the business to target business goals while keeping code base simple, efficient and maintainable. I know how to organize development from client requirements to production deployment. I want to work on fresh startups and build web apps from scratch. And I'm looking for long-term relationships. My skills: — Ruby (Ruby on Rails, Sinatra, Grape) — ReactJS, AngularJS — DB: MySQL / PostgreSQL / Redis / Mongo — Cloud hosting: DigitalOcean / AWS / Heroku — API integration: Facebook, Twitter, Instagram, Braintree, Stripe and others If you are ready to get started just click the contact button and we will rock that party.

With over 13 years of experience and 14,000+ hours on Upwork, I create Ruby on Rails web applications that are not only functional but built to last. Able to take a project at any stage — from an initial idea to a complex, production-ready system — and manage every aspect: backend architecture, integrations, performance optimization, and long-term maintenance. I have successfully delivered large-scale projects across multiple domains — from a hotel booking engine to a fintech platform for investors, a job search and recruitment platform and many others. I leverage modern tools such as GitHub Copilot for documentation, autocomplete, code optimization, and SQL query improvements, while using AI assistants like ChatGPT and Gemini to speed up research and handle small tasks such as generating regular expressions. I also understand the importance of AI in boosting development speed, productivity, and automation, and apply it thoughtfully to enhance my workflow without compromising code quality. Whether you need to launch a new product, rescue a struggling codebase, or scale your existing platform, I bring the skills, reliability, and insight to get it done right the first time.

👋 I'm a Senior Full Stack Java Developer with 20+ years of experience building enterprise software, healthcare platforms, fintech solutions, SaaS products, and mobile applications. As a Java Developer I've built high-load backend systems, REST AP payment solutions document processing platforms, and business applications used by thousands of users. As a Full Stack Developer and React Native Developer I've helped startups and growing companies launch scalable products while maintaining security, performance, and compliance. Throughout my career, I've worked with startups, established businesses, and enterprise clients, helping them transform ideas into reliable software products. My experience covers the entire development lifecycle, from architecture planning and technical discovery to development, deployment, optimization, and long-term support. My expertise includes Java Developer Spring Boot React Native AWS PostgreSQL Docker Kubernetes microservices cloud infrastructure and secure software architecture 💪 Full Stack Java Developer Expertise ✔️ 20+ years of Java development 100 successful projects using Java, Spring Boot, Spring Security, Hibernate, and enterprise architectures ✔️ Full Stack Development covering backend architecture database design frontend implementation and React Native mobile applications ✔️ Spring Boot Development, REST API microservices cloud-native applications and high-performance backend systems ✔️ Backend Architecture, distributed systems, 50 third-party integrations, authentication systems, and secure API development ✔️ PostgreSQL MySQL Redis AWS Docker Kubernetes CI/CD performance optimization and legacy system modernization ✔️ Extensive experience designing business-critical applications where scalability, maintainability, security, and long-term growth are key requirements ✔️ Experience integrating payment gateways, healthcare systems, cloud services, identity providers, and external enterprise platforms ✔️ Strong understanding of software architecture, design patterns, clean code principles, and modern development practices ✔️ Experience leading technical initiatives, collaborating with distributed teams, participating in code reviews, and helping businesses make technology decisions 🏥 Healthcare Software Development Expertise As a Senior Java Developer and Full Stack Developer, I've built secure and HIPAA-compliant healthcare software for startups, clinics, and digital health companies. ✔️ 100+ healthcare applications including EHR/EMR systems, telemedicine platforms, patient portals, and engagement solutions ✔️ 80+ FHIR & HL7 integrations for healthcare interoperability and secure data exchange ✔️ 150 React Native healthcare apps with Apple HealthKit, Google Fit, BLE, and real-time health monitoring ✔️ 100+ healthcare features delivered, improving patient engagement and clinical workflows ✔️ 50+ HIPAA-compliant architectures with encrypted storage, audit logging, RBAC, and secure APIs ✔️ 100 Java Spring Boot backend systems with up to 99.9% uptime ✔️150+ healthcare workflow automations, provider portals, appointment management, and patient communication platforms 💳 Fintech Software Development Expertise As a Full Stack Java Developer I've built PCI DSS-compliant fintech platforms focused on payments, identity verification, and transaction security. ✔️ 30+ Stripe, Apple Pay, Google Pay, and 3D Secure (3DS) integrations ✔️ 20+ KYC & AML workflows for onboarding and compliance automation ✔️ 100+ payment features delivered, reducing friction and improving transaction success ✔️ 25+ payment platforms, transaction systems, and financial API integrations ✔️ 15+ PCI DSS architectures with encryption, tokenization, audit logging, and secure authentication ✔️ 50+ financial reporting, payment workflows, transaction monitoring, and compliance solution 🏆 Key Results ✔️ 20+ years of commercial experience as a Full Stack Java Developer ✔️ 100+ enterprise projects across Healthcare, FinTech, SaaS, and AI ✔️ 55+ AI-powered products using OpenAI, Claude API, FastAPI, AI Agents & RAG ✔️ Up to 100% uptime for mission-critical healthcare and fintech systems ✔️ Up to 40% higher patient engagement through digital health solutions ✔️ Up to 25% lower payment decline rates with optimized payment workflows ✔️ Up to 35% faster application performance and scalability improvements ✔️ Up to 90% fewer security vulnerabilities with secure architectures 📌 Core Technologies Java Developer • Spring Boot • Spring Security • React Native • TypeScript • PostgreSQL • MySQL • Redis • Kafka • AWS • Docker • Kubernetes • REST API • Microservices • HIPAA • Stripe 📩 Looking for a technical partner who understands both technology and business goals? I help companies build, scale, and modernize Healthcare Fintech SaaS and Enterprise products using Java Spring Boot Full Stack technologies and React Native If you're looking for more than just code, let's discuss your project and how I can help.