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15+ years building enterprise Java/ZK Framework systems; over the past 2 years I've shifted focus to AI engineering — Kiro, Bedrock, RAG pipelines, MCP integrations.

AVAILABLE FOR URGENT PROJECTS OR BUG FIXES 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

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

Hey, see you're looking at my profile 😉 Nice to meet you! I'm a 𝗝𝗮𝘃𝗮 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗲𝗿 𝗮𝗻𝗱 𝗙𝘂𝗹𝗹 𝗦𝘁𝗮𝗰𝗸 𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗲𝗿 with 6+ years of experience building backend systems, SaaS applications, software platforms, web applications, and enterprise systems for clients across fintech, logistics, telecommunications, retail, healthcare, and SaaS. As a Java Developer and full stack developer, I design, build, and ship production-ready software systems and platforms end-to-end: architecture, backend, frontend, and deployment. On the backend, my core stack is Java, Core Java, Spring Boot, and Spring Framework, building REST APIs, microservices, and scalable software systems with Hibernate/JPA, SQL, PostgreSQL, MySQL, and MongoDB. As a Java backend developer, I've designed 120+ REST APIs and built 10+ microservice architectures for systems and platforms serving 10K to 500K+ users. I've shipped 35+ production software systems, platforms, and web applications as a full stack developer and Java developer. On the frontend, I build with React, Angular, JavaScript, and TypeScript, delivering full stack web applications and SaaS platforms where clean UI meets solid backend architecture. Whether it's a software system, an internal platform, or a customer-facing SaaS product, I work across the whole stack to make sure the system holds up in production. For infrastructure, I work with AWS, GCP, and Azure, using Docker, Kubernetes, and CI/CD pipelines to keep systems, platforms, and software reliable at scale. The software systems and platforms I've maintained as a full stack developer and Java developer have held 99.9% uptime — the result of solid monitoring, careful deployment practices, and proactive system design. Performance is something I take seriously on every platform and system I build: as a Java Developer, I've cut API response times by up to 60% and improved overall system performance by 40%+ through targeted software architecture improvements rather than costly rewrites. I've also worked extensively with enterprise-level database schemas, optimizing complex SQL queries and data models across tables with 100K+ records. Beyond Java, I also write Python, PHP, and Node.js when a software system or platform calls for it, and I've worked on .NET/C# projects too, including reviving a legacy .NET system onto currently supported frameworks. As a full stack developer, I go where the project needs me. Java is my strongest ground, but I adapt the stack to the system. As a Java Developer, I've also earned certifications in Java Backend API Development and Java Microservices Engineering — production depth, not just a keyword on a profile. Beyond hands-on development, I've led teams, mentored junior developers, and managed cross-functional projects across software systems and SaaS platforms. My clients get clear communication, fast responses, and maintainable software code that still makes sense six months later. 🤝 Let's talk I'm open to long-term collaborations as a Java Developer or Full Stack Developer — Spring Boot, backend systems, SaaS platforms, enterprise software, microservices, and web applications — plus related work in cloud migration, API integration, database optimization, and legacy system modernization. If you need a Java Developer or Full Stack Developer who ships reliable SaaS platforms and software, let's talk.

Freelance IT Specialist | Software Engineer Delivering innovative, high-performance systems for over 17 years. I'm focused on complex system development, I’ve built scalable, resilient solutions for both B2C and B2B environments. Specializing in Java, Spring Boot, Spring Cloud, Maven, PostgreSQL, MySQL, Cassandra, MongoDB, RabbitMQ, and Azure Service Bus, I also bring expertise in technologies like Docker, Dropwizard, Kafka, Zookeeper, AWS. I design architectures that handle evolving demands with ease, integrating third-party systems seamlessly. I know how to design and implement complex systems from scratch, and I excel at supporting and revamping existing (legacy) systems to breathe new life into them. I’m always eager to explore and research new software, evaluating it for potential use in optimizing solutions and driving innovation. A few things I value: Collaborative mindset: I thrive in team environments where communication, trust, and shared goals drive the project forward. My leadership style is about guiding and sharing knowledge, not controlling - empowering teams to innovate while staying focused on delivering results. Precision: I’m committed to delivering clean, maintainable code with robust documentation. From Javadocs to Confluence pages, I ensure clarity so that my work remains accessible and easy to evolve. Every part of the system is documented, covering CI/CD setups and module-specific details. Testing is my backbone: Quality control isn’t an afterthought - it’s built into every stage of development. My philosophy extends beyond unit tests, incorporating performance testing to ensure scalability under real-world conditions. Eternal learner and innovator: Technology doesn’t stand still, and neither do I. I’m constantly exploring new methodologies, frameworks, and ideas to bring fresh insights to my work. From AI-driven automation to future-proofing system architectures, I’m always on the lookout for ways to elevate what’s possible. Freelancer with passion: As a freelancer, every project excites me like it’s my first. I thrive in fast-moving environments and love collaborating with teams to create software that not only meets immediate needs but anticipates future challenges. I’m committed to delivering innovations that matter and clean code that future developers will thank me for. What sets me apart? I bring a holistic approach, ensuring systems are not just functional but scalable, adaptable, and maintainable. From designing complex microservice architectures to ensuring third-party integrations are seamless, I focus on building systems that deliver real, lasting impact. More than just code, I care about the people and businesses behind the software. The right technology can make workflows smoother, interactions richer, and systems smarter - and I’m passionate about helping bring those transformations to life. If you’re searching for someone who combines deep technical expertise with a drive for innovation and quality, I’m ready to partner with you to build the future. Let’s create something remarkable together. P.S. If you’ve made it to this line, the very end of this long read, just tell me and I’ll give you a discount for your patience!

I'm a Java/Spring Boot backend developer with 6 years of experience across CRM, loyalty, and B2B enterprise platforms — the kind of engineer companies bring in when they need someone who can own a backend end-to-end, not just close tickets. ▪️Performance & scale: On a CRM platform for a solar-installation company, I rebuilt the MongoDB query and indexing strategy and cut execution times by 10x or more across reporting, analytics, and core workflows. ▪️Integrations & automation: I've implemented OAuth2 single sign-on so partner dashboards open with one click from inside a CRM, synced schedules via the Google Calendar API, and set up Apache Kafka producers/consumers to move CRM events into async workflows. I've also built a scheduled pipeline that pulls, deduplicates, and standardizes data from a public research API, with no manual cleanup required. ▪️Ownership & delivery: I led an AI-powered CRM analytics feature from concept to production, including the GitHub Actions CI/CD pipeline that deploys it — end to end, without handing off to another specialist. ▪️Legacy & modernization: I'm comfortable in codebases I didn't write. I converted an aging JSP-based Java server into a proper JSON REST API for mobile compatibility. ▪️I spent 19 months adding features to an inherited application (Sweet Home 3D) without breaking what already worked. ▪️I also built resilient HTTP clients in Node.js (proxy rotation, rate limiting, retry logic) when a project calls for it. ✅ Skill: Backend: Java (8/11/17/21), Spring Boot, Spring Data JPA, Spring Security, Hibernate, Apache Kafka Principles: OOP, SOLID, TDD, GOF Design Patterns; Frontend: CSS/HTML, JavaScript/TypeScript; Databases: SQL (PostgreSQL, MySQL), MongoDB; APIs: REST, JSON/XML, Swagger/OpenAPI; Testing: JUnit, Mockito, TestContainers; DevOps: Docker, Maven, Git, GitHub Actions; Top Rated on Upwork, $10K+ earned across 23 contracts and 619 hours, tagged "Clear Communicator" by 4 separate clients. Please tell me what you're building or what's broken, and I'll tell you honestly what it'll take to fix or ship it.