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Need a backend, full-stack, or AI system that holds up in production, not just on a demo branch? That's what I do. I'm a senior software engineer with 6+ years building web apps, desktop products, data platforms, and enterprise integrations for clients in the US, Canada, and Europe. Clients usually come to me with one of these problems: - "Our API is slow or falls over under load." I profile it, fix the queries and caching, and add retries, idempotency, and monitoring so failures stop reaching your users. - "We need a real product, not a prototype." Secure auth, roles and permissions, billing, background jobs, licensing, automated tests, and CI/CD are part of the build, not a phase two. - "We want AI over our own documents but it keeps answering wrong." I build RAG pipelines with hybrid search, reranking, and measured retrieval quality so answers are traceable. - "Our legacy mainframe code needs to run somewhere modern." I deploy and repair COBOL/CICS/DB2/JCL systems on z/OS and IBM Cloud. WHAT I WORK WITH Backend: .NET Core, Python, FastAPI, Node.js, REST APIs, Clean Architecture, CQRS, Kafka, MassTransit, SignalR, Hangfire Frontend: Angular, React, Next.js, TypeScript, RxJS, NgRx, Tailwind, Material UI Data: PostgreSQL, SQL Server, MongoDB, Redis, Qdrant, pgvector AI: RAG, LangChain, OpenAI, Cohere, hybrid vector + BM25 search, reranking, evaluation Cloud and DevOps: AWS, Azure, IBM Cloud, Docker, GitHub Actions, Azure DevOps, xUnit, pytest Mainframe: z/OS, COBOL, CICS, DB2, VSAM, JCL WHAT I'VE DELIVERED - A multi-tenant vendor risk platform covering supplier onboarding through audits and remediation, with enterprise SSO, granular permissions, Stripe billing, and AWS deployment. - Three years on a freight-forwarding ERP: 1,000+ endpoints, 25+ carrier and accounting integrations, and the full rate-to-shipment lifecycle. - A licensed Windows and macOS desktop product with signed entitlements, offline grace periods, and crash-recovery testing. - A multilingual vehicle-manual chatbot with intent classification and an automated retrieval-evaluation harness. - Technical leadership of a 6-developer team across architecture, estimation, and releases. HOW I WORK I plan carefully before writing code, clarify anything that is unclear, and provide an honest estimate before development begins. I will also tell you early if an approach is risky or unlikely to work. You will receive working increments that you can review throughout the project - not a month of silence followed by unexpected results. I always take ownership of project and meet the deadline I commit to. I have maintained a 100% Job Success Score and delivered more than 2,400 hours of work on Upwork. Some of my project details are in my portfolio and work history below. Send me your requirements, and I will reply with a clear technical approach, the main trade-offs, and a realistic delivery timeline.

13+ years experienced in Java/J2EE | AWS Certified(SAA , DVA, CloudOps) | Java Professional Certified | Docker | Kubernetes | Rest API | Spring boot | Spring AI | Microservices| Spring Security | JPA | Oracle | Mysql | Process Mining | MCP | OpenAI | OPENAPI I React Js| ZK UI | Grafana | Prometheus | EJB Certified | 7 years in Financial or Banking application | Agile/Scrum | Lead Team.

Java & Spring Boot Architect | AI-Powered Backend Systems | 14+ Years Experience I am a Java & Spring Boot architect with 14+ years of hands-on experience building production-grade enterprise systems — from core banking platforms to AI-integrated microservices. I hold a BSc in Computer Science & Technology and now work as a dedicated full-time freelancer on Upwork, bringing the same rigour I applied in large fintech institutions directly to client projects. My core expertise spans Spring Boot, Spring Framework, and microservices architecture, with deep practical knowledge of SSO & Keycloak, Docker, DevOps pipelines, and GitLab CI/CD. I design systems that are secure, observable, and built to scale — whether that means integrating Kafka for event-driven flows, Flowable BPMN for workflow automation, or AWS for cloud infrastructure. Over the past year I have been heavily invested in the AI/LLM frontier: building Spring AI applications, wiring up MCP (Model Context Protocol) servers, running local models via Ollama, and implementing advanced patterns like tool calling, RAG pipelines, and AI agent workflows. I see AI not as a separate layer but as a first-class citizen inside enterprise Java backends. If you need someone who understands both the old-school reliability of enterprise Java and the new possibilities of AI-augmented architecture — let's talk. CORE STACK: Java · Spring Boot · Spring Framework · Microservices · REST API · Keycloak/SSO · Docker · GitLab CI/CD · DevOps · Kafka · Flowable BPMN · Oracle · PostgreSQL · AWS · Angular AI & EMERGING TECH: Spring AI · MCP · Ollama · Tool Calling · AI Agents · RAG Pipelines · pgvector · LLM Integration · OpenAI API · Prompt Engineering DOMAINS: Banking & Fintech · SWIFT/ISO 8583 · AML/CFT Compliance · NPSB/RTGS · ATM Switch · eKYC · Healthcare/EMR · Document Management

More than 21 years of experience on Java/JEE, PHP, C, C++, Perl, Shell Script, JavaScript MySql and Oracle technologies. An experienced Software Engineer/Architect with having strong R&D[Research & Development] background. Enjoy working on research based development, creating API/SDK, application framework and performance engineering, testing, code profiling, code optimizing, query optimizing, team and project managing. Experienced in designing Cloud computing/service, Semantic web, Sensor network, Ontology, SSO/Identity management, Asynchronous architecture, Mobile based App[Android] Data collector[xForm], Asterisk[AMI/AGI] based interactive IVR application, mHealth, e-Education, disaster and early warning system, Courier & Freight Software, Warehouse & Retail Supply Chain Software, Corporate Mailroom Software, Travel Software, Billing software and Web Bot. Wide and deep knowledge in Java/JEE Technology & OOP Architecture, REST/RESTful architecture, design patterns. Experience in Business intelligence and Reporting Tool. Workflow and BPMS. RDBMS. Solid background in Object-Oriented analysis and design UML, Design Patterns, Architecture Patterns and Software development methodology (Agile/SCRUM/TDD). Technical experienced on Java/JEE, EJB3.0, Spring, Hibernate, JPA, JSF, RichFaces , PrimeFaces Wicket, Struts, DWR, GWT, AngularJS, PhantomJS, Android, HTML, CSS, JS, jQuery, JAX-WS, JAX-RS, SOAP, Maven, Gradle, Jenkins , CloudBees, Google App Engine, Amazon AWS, jBPM , ESB, Node.js ,MySQL, ORACLE, PostgreSQL, SQL Server, MongoDB etc My preference to work on long term project. It could be hourly or fixed price job but hourly job is my first preference. I would like to maintain trustworthily long term relationship through good work. If anyone is there on the same page and match my criteria please poke me for further... More details about technical skills --------------------------------------------------------------------- Programming Languages: J2EE/J2SE/J2ME, Scala, JRuby, C/C++, Assembly, HTML/HTML5 /DHTML/ XHTML, JavaScript, Ajax, XML/XSL, PHP, Android. Frameworks & Toolkits: Spring, EJB3.0, JPA, Hibernate, S2Dao, S2Hibernate, Seasar, JSF, RichFaces, PrimeFaces, Wicket, Struts, DWR, SWT, GWT, Facelets, MIDP 2.0, JavaRosa, Smarty, ADODB, Yii, CodeIgniter, Laravel, Node.js, Dojo, jQuery, AngularJS, PhantomJS. GUI's: SWT, Eclipse RCP & RAP, JFace, Swing/JFC, AWT, JavaDesktop, Java2D, JGoodies. Databases: Oracle, MYSQL, PostgreSQL, MongoDB, SQL Server, JavaDB, FireBird, HSQL Template Languages: Apache Velocity, Handlebars, Nunjucks Build and Logging Tools : Apache Ant, Maven, Gradle , Jenkins , Log4j, gulp, Liquibase Application Servers: Glassfish, Tomcat, WildFly, WebLogic, Jetty Testing Tools: Selenium, JUnit, EasyMock, Mockito, Mercury LoadRunner, JMeter, BlazeMeter. XML's: XML (Dom, Xerces), XPath, Schema, XSD, RDF, Xform (openrosa & javarosa). Workflow (BPMS) & ETL: jBPM, Kettle, Talend. Business Intelligence & Reporting Tool: Eclipse BIRT, Pentaho, JasperRepors. IDE's: Eclipse, NetBeans, IntelliJ, MyEclipse Project Management Tools: SFEE (Source Forge Enterprise Edition), Subversion, Mylyn, Version One, Target process, JIRA, WorkFront, Asana, Redmine, CVS, SVN, GIT, Marcural Methodologies: RUP, Agile, XP, Scrum Operating Systems: Sun-Solaris-x86(10), Linux Family (Redhat/obuntu/Suse), Windows Family (NT/XP/98/2000/2003, vista).