Homan SarwarySoftware Developer & AI Agency
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.
Senior Java Backend Developer Focused on Cloud Native & Microservices
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:
- Architecture and implementation of Microservices with Java and Spring Framework
- Conception and development of domain models following Domain-Driven Design (DDD)
- Development of web services with RESTful APIs and SOAP
- Use of Spring Boot, Spring MVC, Spring Data, Spring Security
- Persistence solutions with JPA (Java Persistence API) and the Hibernate framework
- Messaging with JMS (Java Messaging API) as well as Kafka, ActiveMQ, and RabbitMQ
- Interface coordination with internal and external stakeholders
- Software development for cloud technologies such as AWS, OpenShift/Kubernetes, and Microsoft Azure
- Test automation with JUnit, Mockito, and the Cucumber Framework (BDD)
- Software architecture, system design, and evolution of existing system landscapes
- Coaching & Training
- Scrum Master activities
- Analysis of requirements and writing of User Stories (Business Analyst)
- AI integration & Prompt Engineering in software development
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.
My Three Core Services
As a Java Cloud Native Developer I bring focused expertise in three strategic areas for your enterprise project.
Microservice Architecture
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.
- Domain-Driven Design & Clean Architecture
- Microservice Design & Interface Architecture
- RESTful APIs, OpenAPI/Swagger, Consumer-Driven Contracts
- Interface alignment, clarification & adaptation with third-party providers
- Event-Driven Architecture with Apache Kafka
Backend Development
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.
- Java SE/EE 8–21, Spring Boot, Spring Framework
- Apache Kafka & Event-Driven Systems
- JPA / Hibernate & Database Integration
- TDD, BDD (Cucumber), JUnit & Test Automation
Cloud Native Development
Migration and development of applications for cloud environments as a Java Cloud Architect – with AWS and Azure, Docker, Kubernetes, and modern CI/CD pipelines.
- AWS & Azure Cloud Platforms
- Docker & Kubernetes / OpenShift
- CI/CD Pipelines (Jenkins, GitLab CI)
- Cloud Migration & Performance Optimisation
Why Clients Work With Me
As a Senior Java Backend Developer with proven enterprise experience I offer clear advantages for critical backend projects.
10+ Years Java Enterprise
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.
Banking & Large Organisations
Project experience at ING, Comdirect, Commerzbank, and Deutsche Bahn – in highly regulated environments with the highest requirements for stability, security, and scalability.
Scalable Cloud Architectures
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.
Agile Development & DevOps
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 in Software Development
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.
Technology Stack
Core competencies of an experienced Java Consultant and Spring Boot Freelancer – focused on the technologies that make enterprise systems scalable and future-proof.
Technical Expertise
Methods & Frameworks
Selected Projects
Over 10 years of project experience at leading organisations in banking, automotive, rail, and aviation.
Software Engineer / Java Backend Developer
IT Consultant / Java Software Developer
- Design and implementation of new components using Java SE and Spring within a monolithic system landscape
- Integration of the Cucumber framework for test automation (BDD)
- Analysis of business requirements and derivation of technical solutions
- Technical point of contact and advisory for the development team
- Active Scrum Master duties: reviews & sprint planning
Software Engineer / Java Backend Developer
IT Consultant / Java Software Developer
- Data modelling and further development of existing data models for a new card processor
- Design and implementation of a new data model for processing transactions (payment processing) using Spring Batch
- Development and optimisation of Spring Batch jobs for transaction processing
- Analysis of business requirements and elaboration of user stories
- Documentation of the architecture in Confluence, regular status reporting
Software Engineer / Java Backend Developer
IT Consultant / Java Software Developer
- Design and implementation of portal components using Java and Spring within a Microservices architecture
- Development of API services based on RESTful and Spring MVC
- Coordination and definition of interfaces including initial interface tests
- Scrum Master duties including Scrum reviews and planning
Software Engineer / Java Backend Developer
IT Consultant / Java Software Developer
- Development of a platform for connected vehicles
- Design and implementation of real-time data transfer components
- Building interfaces and REST APIs with Spring Reactive (RxJava 3)
- Technical consulting on architecture and implementation options
API Development for Asset/Configuration Management
IT Consultant / Java Software Developer
- Design and implementation of RESTful APIs using Java SE 11 and Spring
- Development of API services for transferring configuration data (AWS, uCMDB) into asset management systems
- Implementation on the DB Systel BizHub
- API-First and Contract-First approach, JWT security, and OWASP penetration testing
Backend Application for DB Sales – Customer Account (KTO)
IT Consultant / Java Software Developer
- Development of the central customer account component of the new DB sales platform as a fault-tolerant REST service in the AWS cloud
- Representation of the development team in cross-project architecture and security committees
- Consumer-Driven Contracts (CDCs), Microservice conception, interface testing
- Technical point of contact for business analysts and product owners
Lead Trainer – Java Standard Edition (Java SE)
Java SE Trainer
- Conducting Java SE seminars and targeted preparation for Oracle certification OCA Java SE 8 (1Z0-808)
- Communicating complex technical concepts to groups of participants
- Facilitating learning content and deepening communication and moderation skills
Customer Onboarding Platform (International Project)
IT Consultant / Java Software Developer
- Development based on an SOA architecture with SOAP and RESTful services
- Coordination and alignment with Indian development partners (offshore)
Further Development – Flight Licence Management
IT Consultant / Java Software Developer
- Conception and creation of a requirements specification
- Extension of the domain model and development of new components based on SOAP and EJB
Java Tutor – Programming 1 & 2
Subject Tutor / Lecturer
- Conducting Programming 1 & 2 seminars using Java for Computer Science students
- Preparation and delivery of lectures as well as individual student support
- 5 years of teaching – building communication, facilitation and coaching skills
Recognised Certifications
What Clients Say
„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."
Honar IT – Your AI Agency for Enterprise & Mid-Market
From AI consulting and Claude integrations to automation solutions and training – everything from a single source, with 10+ years of enterprise experience.
Our 6 Service Areas
RAG Systems on Enterprise Data
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.
Process Automation with AI Agents
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 →LLM Backend Integration
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.
AI Consulting & Strategy
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.
AI Training & Workshops
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.
AI Readiness Assessment & PoC
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.
"We don't build AI demos. We integrate AI into systems that cannot afford to fail."
Why Honar IT as Your AI Agency?
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.
Our AI Technology Stack
Modern Websites & Web Applications
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.
Landing Pages & Corporate Sites
Professional corporate websites and landing pages with clear structure, strong impact, and technical quality. Fully responsive, Lighthouse-optimised, and GDPR-compliant.
- Responsive Design – Mobile-first
- SEO optimisation & Core Web Vitals
- Performance optimisation & fast load times
- GDPR-compliant implementation
Web Apps & Single-Page Applications
Complex interactive web applications with modern frameworks. From dynamic dashboards to database-backed platforms – cleanly architected and maintainable.
- React / JavaScript / TypeScript
- Component-based architecture
- State management & API integration
- Testing & CI/CD integration
Full Stack & Backend Integration
Seamless connection of modern frontend and Java backend. REST APIs, Spring MVC, database connectivity, and deployment on cloud infrastructure – all from one source.
- Spring Boot / Spring MVC REST APIs
- Java backend integration
- Database connectivity (SQL / NoSQL)
- Cloud deployment (AWS / Azure)
E-Commerce & Online Shops
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.
- Shopify · WooCommerce · Headless Commerce
- Secure payment (Stripe, PayPal, Klarna)
- Conversion & checkout optimisation
- GDPR-compliant & PCI-DSS-secure
Interested in a website, an online shop, or a web application? Describe your project – I will get back to you within 24 hours.
Frequently Asked Questions
Answers to the most common questions about Java backend development, AI integration and working together.
Which technologies does Homan Sarwary master as a Java freelancer?
Homan Sarwary specialises in Java SE/EE (8–21), Spring Boot, Spring Framework, Apache Kafka, microservices, Domain-Driven Design, Kubernetes, Docker, AWS and Azure.
Where does Homan Sarwary work as a Java consultant?
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.
How much experience does Homan Sarwary have as a Spring Boot freelancer?
Homan Sarwary has more than 10 years of experience as a Java backend developer, including projects at ING, Comdirect, Commerzbank and Deutsche Bahn.
Which certifications does Homan Sarwary hold?
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.
What does Honar IT do as an AI agency?
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.
Which AI technologies does Honar IT use?
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.
Can AI be integrated into existing Java backend systems?
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.
Which engagement models and rates does Honar IT offer?
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.
How quickly can an AI proof of concept be delivered?
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.
In which industries does Homan Sarwary have experience?
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.
Ready for Your Next Project?
Check my current availability on FreelancerMap or get in touch directly – I look forward to your enquiry.
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