Senior Java Backend & Cloud Native Developer for Scalable Microservice Systems
Java Freelancer · since 2016 · Frankfurt am Main · DACH (DE · CH · AT)
I help companies develop high-performance backend systems using the Java programming language and the Spring Framework for scalable modern cloud platforms like Kubernetes and AWS. As an experienced Java consultant, I bring over 10 years of enterprise project experience in banks and large corporations, as well as expertise in AI integration in software development.
Since April 2016 I have been developing modern, scalable, and proven software solutions.
My focus is on developing Cloud-Native applications based on Java SE and Java EE and the Spring Framework, applying agile methods such as Scrum and SAFe and DevOps principles.
My key areas of expertise include in particular:
As a Java tutor I gained valuable experience in team coaching and applied it successfully in projects. As lead trainer for Java Standard Edition and certification preparation I prepared groups of participants for the exam. I facilitated learning content, conveyed complex technical concepts in a practical way, and deepened my communication and facilitation skills.
Through my involvement in complex large-scale projects I am experienced in successfully managing the interface between internal and external stakeholders. I coordinate and ensure technical alignment across system and team boundaries. I work in a structured, patient, and communicative manner within teams and pick up new technologies quickly. I continuously monitor current frameworks and development trends and actively bring new ideas into the team.
As a Java Cloud Native Developer I bring focused expertise in three strategic areas for your enterprise project.
Design and modernisation of scalable enterprise systems as an experienced Microservices Developer. Conception based on Domain-Driven Design, Consumer-Driven Contracts, and API-First – with Java, Spring Boot, and Spring Cloud.
Robust, high-performance backend services as an experienced Java Consultant for enterprise systems in banking and large organisations. Full Spring ecosystem, JPA, Kafka, and test automation.
Migration and development of applications for cloud environments as a Java Cloud Architect – with AWS and Azure, Docker, Kubernetes, and modern CI/CD pipelines.
As a Senior Java Backend Developer with proven enterprise experience I offer clear advantages for critical backend projects.
Over a decade of experience developing complex Java backend systems – from architecture through to production-ready solutions. As a Spring Boot Freelancer with a demonstrated track record in demanding projects.
Project experience at ING, Comdirect, Commerzbank, and Deutsche Bahn – in highly regulated environments with the highest requirements for stability, security, and scalability.
Focus on future-proof, cloud-native Microservice architectures with AWS, Azure, Kubernetes, and Apache Kafka. Solutions that grow with your business – as an experienced Microservices Developer and Java Cloud Architect.
Certified Scrum Master (PSM I & II) with a lived DevOps culture. CI/CD, automated testing, and continuous integration from day one – for fast delivery cycles and stable systems.
AI integration as a fixed part of my daily development work – with GitHub Copilot as an AI pair-programmer in the IntelliJ IDE, OpenAI API and Claude API for LLM integrations in Java backend systems, and Spring AI for Java-native AI connectivity with RAG pipelines and embeddings.
Core competencies of an experienced Java Consultant and Spring Boot Freelancer – focused on the technologies that make enterprise systems scalable and future-proof.
Over 10 years of project experience at leading organisations in banking, automotive, rail, and aviation.
IT Consultant / Java Software Developer
IT Consultant / Java Software Developer
IT Consultant / Java Software Developer
IT Consultant / Java Software Developer
IT Consultant / Java Software Developer
IT Consultant / Java Software Developer
Java SE Trainer
IT Consultant / Java Software Developer
IT Consultant / Java Software Developer
Subject Tutor / Lecturer
„Homan hat sich sehr schnell in das KTO-Development-Team integriert, die Rituale unseres SCRUM-Teams aktiv mitgestaltet und durch seine sachliche und ruhige Art zur Klärung von hitzigen Diskussionen beigetragen. Er hat sich zum Experten für Spring Boot, Spring REST Services, OpenAPI (Swagger), Spring Cloud Contracts und Cucumber entwickelt. Neben seiner Programmiertätigkeit hat er das Team im Architektur- und Security-Gremium vertreten und als Ansprechpartner für andere Teams fungiert. Er wird dem Team sehr fehlen."
„Homan hat sich sehr schnell in das Squad integriert und selbständig Aufgaben übernommen. Er hat aktiv an den Entwicklungsthemen mitgearbeitet und viele Verbesserungsvorschläge eingebracht. Seine Schwerpunkte lagen in Java SE/EE, RESTful APIs, Spring Framework, Apache Kafka, Testautomatisierung, Cloud-Technologien, Kubernetes, Azure, Microservices und ShedLock. Wir würden ihn jederzeit gerne wieder bei uns einsetzen."
From AI consulting and Claude integrations to automation solutions and training – everything from a single source, with 10+ years of enterprise experience.
Intelligent search and analysis across internal knowledge bases (Confluence, SharePoint, internal docs) based on Claude + RAG pipelines. Securely integrated into existing Java systems without sending sensitive data to external APIs in an uncontrolled manner.
Claude agents integrated directly into Spring Boot microservices. Document verification, compliance checks, email triage – with Kafka connectivity, retry logic, observability, and CI/CD pipeline.
Submit automation request →Direct integration of LLMs (Claude, GPT-4o) into Java/Spring backend systems. REST APIs with AI capabilities, streaming responses, tool use, and prompt caching – production-ready, scalable, and cost-optimised.
Strategic consulting: Where does AI add value in your organisation? We analyse your processes, evaluate AI potential, and deliver a prioritised roadmap – free of vendor lock-in, neutral and results-oriented.
Practical training for developers and teams: Prompt Engineering, Claude API, Agentic AI, Spring AI integration. From half-day workshops to multi-day intensive courses – remote or on-site.
From assessment to working proof of concept in 4–6 weeks. We identify the 2–3 processes with the highest AI leverage and build a functional prototype using Claude API.
You bring your domain know-how, we bring the technical delivery. Together we build an AI solution that creates measurable economic value – from the initial situation through to support after go-live.
You contribute your domain know-how, we bring the technical perspective. Together we clarify the starting point, constraints and goals.
We identify the use cases with the greatest leverage and prioritise them by economic value and feasibility.
Joint architecture decisions: we contribute the technical know-how for a robust, secure and scalable solution.
Production-ready implementation and integration into your existing systems – with a guided, plannable go-live.
Support after go-live: further development and support as needed – so the solution delivers value in the long term.
Solutions that pay off – with a clear view of costs and benefits.
Defined KPIs instead of vague promises: the benefit becomes measurable.
Efficiency gains that feed into your revenue and cost calculations.
"We don't build AI demos. We integrate AI into systems that cannot afford to fail."
10+ years in banking and large corporations. We know the requirements for stability, security, and compliance from first-hand project experience.
While others offer every LLM, we master the Anthropic API in depth: Extended Thinking, Tool Use, Streaming, Prompt Caching.
No Python workarounds. Direct integration into your Java/Spring landscape via Spring AI and LangChain4j.
From consulting through development to team training. One point of contact, one consistent approach.
We build with AI at the core: agentic engineering with Claude Code and modern AI-dev workflows – delivering faster at consistent enterprise quality.
Systematic prompt & context engineering: RAG, context windows and caching deliberately orchestrated for reliable, reproducible LLM results.
I have written and published two professional books on Anthropic Claude – from the first prompt through production-ready agent systems to the official Claude certification, CCA-F. (Both books are written in German.)
From the first prompt to a production-ready agent system: the six core prompt-engineering techniques, the Claude Agent SDK, MCP integrations, plus security and compliance (EU AI Act, GDPR) – with three end-to-end projects and six DACH case studies.
View on epubli →
A precise preparation for the Claude Certified Architect – Foundations (CCA-F), the first official technical certification from Anthropic. Structured along the five weighted exam domains D1–D5 – no external material required.
View on epubli →From professional corporate websites and interactive single-page applications to high-converting online shops and fully backend-integrated web platforms – performant, SEO-optimised, and mobile-ready.
Professional corporate websites and landing pages with clear structure, strong impact, and technical quality. Fully responsive, Lighthouse-optimised, and GDPR-compliant.
Complex interactive web applications with modern frameworks. From dynamic dashboards to database-backed platforms – cleanly architected and maintainable.
Seamless connection of modern frontend and Java backend. REST APIs, Spring MVC, database connectivity, and deployment on cloud infrastructure – all from one source.
Online shops that don’t just look good – they sell. From lean Shopify and WooCommerce stores to bespoke headless-commerce platforms with a Java backend – conversion-optimised, lightning-fast, and secure at checkout.
Interested in a website, an online shop, or a web application? Describe your project – I will get back to you within 24 hours.
Answers to the most common questions about Java backend development, AI integration and working together.
Homan Sarwary specialises in Java SE/EE (8–21), Spring Boot, Spring Framework, Apache Kafka, microservices, Domain-Driven Design, Kubernetes, Docker, AWS and Azure.
Homan Sarwary works as a software developer and Java freelancer in Frankfurt am Main, throughout Germany and across the entire DACH region (Germany, Austria, Switzerland) – both on-site and fully remote.
Homan Sarwary has more than 10 years of experience as a Java backend developer, including projects at ING, Comdirect, Commerzbank and Deutsche Bahn.
Homan Sarwary is certified as Professional Scrum Master II (PSM II), Professional Scrum Master I (PSM I), Professional Scrum Product Owner I (PSPO I), Oracle Certified Associate Java SE 8 (OCA) and ISTQB Certified Tester Foundation Level.
Honar IT is an AI agency for enterprise and mid-sized companies, specialising in the Anthropic Claude API. The services include RAG systems on enterprise data, LLM backend integration into Java/Spring systems, process automation with AI agents, AI consulting & strategy, AI training and AI readiness assessments.
Honar IT works with the Anthropic Claude API (extended thinking, tool use, streaming, prompt caching), Spring AI, LangChain4j, the OpenAI API and RAG technologies for vector databases and embeddings – all Java-native, without Python workarounds.
Yes. Honar IT integrates LLMs directly into existing Java/Spring backend systems via Spring AI and LangChain4j. The result is REST APIs with AI features, streaming responses and Kafka connections – without rebuilding the existing infrastructure.
Honar IT works on a project basis or at daily or hourly rates as a freelance developer – remotely across the entire DACH region or on-site in Frankfurt am Main. Options include dedicated project assignments (Java backend, microservices), time-boxed AI integrations and AI readiness assessments with a fixed-price PoC in 4–6 weeks. The specific terms are tailored to each project after a free initial consultation.
Through the AI readiness assessment, Honar IT identifies the processes with the highest AI leverage and builds a working proof of concept with the Claude API within 4–6 weeks. Existing Java/Spring systems are connected without rebuilding the infrastructure.
Homan Sarwary brings more than 10 years of enterprise experience – primarily in the banking and finance sector (ING, Comdirect, Commerzbank), in transport and mobility (Deutsche Bahn) and in the automotive industry (Daimler/Mercedes-Benz). The solutions range from scalable microservice backends to AI integration.
Yes. Homan Sarwary is the author of two published books on the Claude AI platform by Anthropic (publisher epubli, 2026): „Claude KI – Das Praxisbuch“ (ISBN 978-3-565-54635-0) on prompt engineering, the Claude Agent SDK, the Model Context Protocol (MCP) as well as security and compliance, and „Professioneller Leitfaden zu Claude KI“ (ISBN 978-3-565-54667-1) preparing for the official Claude Certified Architect – Foundations (CCA-F) certification. Both books are written in German.
Check my current availability on FreelancerMap or get in touch directly – I look forward to your enquiry.
Whether Java backend, AI integration, process automation, or website – describe your project. I will get back to you within 24 hours.
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