Backend Engineering
- Java
- Spring Boot
- REST APIs
- Microservices
- Distributed Systems
- SQL / PostgreSQL
- Hibernate / JPA
- System Design
Backend Engineer | Java & Spring Boot | Distributed Systems | Fintech & Banking Experience
Backend Engineer with strong experience in Java, Spring Boot, and distributed systems
I build scalable backend services, APIs, and system architectures. I also have domain experience in fintech and banking platforms, as well as e-commerce, CRM, telecommunications, and enterprise software.
7+
Years Backend Experience
70M+
Business Banking Users on Platforms I've Worked On
~90
Chapter lead scope (engineers)
4
Enterprise Companies
2
Startups
Who I Am
Java, Spring Boot, scalable backends, and clear system architecture.
I am a Backend Engineer specializing in Java and Spring Boot, building scalable backend services, REST APIs, and microservice architectures. My work focuses on system design, database design, performance optimization, and distributed systems.
I have experience working on fintech and banking platforms, as well as e-commerce, CRM, telecommunications, and enterprise systems. This gives me strong domain knowledge while keeping my core focus on backend engineering and software architecture.
My main technologies include Java, Spring Boot, Hibernate/JPA, SQL and NoSQL databases, Docker, and cloud-based deployment environments. I enjoy designing clean architectures, well-structured APIs, and systems that are maintainable and scalable.
I am based in Warsaw, Poland and work in international teams in English(C1), Turkish(Native), and Polish (A2).
Read my full storyConsulting Services
Backend architecture, Java/Spring, microservices, APIs, performance—and domain support where finance is in scope.
Backend Architecture Consulting
Design and refine backend systems for scale, reliability, and maintainability.
Learn moreJava & Spring Boot Consulting
Deep expertise in Java ecosystems and Spring Boot best practices.
Learn moreMicroservices Design & Modernization
Design, split, and modernize microservices architectures.
Learn moreFintech & Banking Domain Consulting
Experienced in fintech and banking systems—architecture, integrations, and regulated environments.
Learn moreSystem Scalability & Performance Improvement
Identify and resolve bottlenecks in high-traffic systems.
Learn moreAPI Design & Integration Strategy
Design APIs and integration patterns for internal and external consumers.
Learn moreExpertise
A toolkit built over years of backend development, system architecture, and platform engineering.
Cloud & Infrastructure
- Docker
- CI/CD
- Jenkins
- GitHub Actions
- Monitoring
- Performance Testing
Architecture & Performance
- System Architecture
- Performance Testing
- Load Testing (k6)
- JVM Performance
- Scaling Systems
- Observability
- Logging & Monitoring
- Reliability Engineering
Leadership & Collaboration
- Technical Leadership
- Mentoring Developers
- Code Reviews
- Knowledge Sharing
- Workshops
- Stakeholder Communication
- Project Ownership
- Team Collaboration
AI & Automation
- AI Agents
- Prompt Engineering
- Workflow Automation
- API Integrations
- Data Pipelines
Industries I Serve
Enterprise, e-commerce, telecom, and financial platforms—same engineering discipline across domains.
Enterprise Software
Internal platforms, multi-tenant services, and integrations for large organizations. Emphasis on clear APIs, ownership, and backends that stay maintainable as scope grows.
Learn moreE-commerce
High-traffic backends, order and catalog flows, and integrations with payments and logistics—performance and consistency under load.
Learn moreTelecommunications
CRM and operational systems for telecom: complex domain modeling, integrations, and high-availability expectations.
Learn moreBanking
Business and retail banking and wealth-related platforms at scale. Core banking integrations, regulatory context, and multi-tenant financial deployments—I am experienced in fintech and banking systems in this sense.
Learn moreFintech
Fast-moving product teams that still need reliability and auditability. Architecture and APIs that balance delivery speed with operational maturity.
Learn moreFinancial Services
Enterprise financial software: internal tools, client-facing services, reporting pipelines, and cross-system integrations.
Learn moreWhy Work With Me
Technical depth, cross-domain delivery, and clear ownership of outcomes.
Technical depth
7+ years building backend systems. Java, Spring Boot, microservices—I've shipped and scaled them in production.
Domain breadth
Experienced in fintech and banking systems—and equally at home in e-commerce, CRM, telecommunications, and enterprise backends. Context informs design without defining the whole role.
Business alignment
I connect technical decisions to business outcomes. Architecture that serves growth, not just elegance.
Leadership experience
Chapter Team Lead for ~90 engineers. I know how to guide teams, not just write code.
Selected Experience
Generalized summaries of consulting and engineering work. Some details are confidential.
Banking
Large-Scale Business Banking Platform
Consulting and development for a business banking platform serving tens of millions of users across multiple regions.
Read moreFinancial Services
Enterprise Financial Systems
Backend engineering for enterprise financial systems including internal platforms and client-facing applications.
Read moreE-Commerce
E-Commerce Platform Engineering
Backend support for a large e-commerce platform handling high traffic and complex order workflows.
Read moreWorked Across
Experience from leading technology and financial services companies.
Backbase
EPAM
Vodafone
Etiya
Professional references
What People Say About Me
Chris Ellis
Engineering Leader
Meta
I worked with Yusuf during my time as VP of Engineering at Backbase, where he was part of our wider engineering organisation. Even in a company full of strong Java engineers, Yusuf stood out for the quality and craftsmanship of his code. He brought real d…
Jarno van Hurne
VP Product, SME & Commercial Banking
Backbase
Yusuf has been one of those rare engineers you can trust with the hard, messy problems and know they'll come back not just solved, but cleaned up for the long term. In Backbase he consistently took on high-complexity backend work in our Entitlements capab…
Jasper Linschoten
Lead Principal Backend Engineer
Backbase
In my experience, Yusuf is a solid engineer. Where I saw him exceed expectation is in how he took on his responsibilities as a Chapter Lead in Backbase RnD. Ensuring active cooperation and knowledge sharing between engineers and running an engaging chapte…
Henk Brunt
Senior Product Architect
Backbase
Yusuf joined the Entitlements team almost three years ago as part of the expansion of our Poland development center. From the beginning, already starting during my introductions to the topics, he demonstrated a strong engagement, asking insightful questio…
Amandeep Singh Kochar
Group Product Manager, Head of Central Services
Backbase
I worked with Yusuf at Backbase and appreciated his professionalism, strong work ethic, and positive attitude. He is a reliable engineer who collaborates well with cross-functional teams and is consistently open to feedback and learning. Yusuf approaches…
Erdem Akkuzu
Backend Software Engineer
Etiya
I had the pleasure of working with Yusuf at two different stages of our careers. We first met back in 2019 at Etiya, when we were both junior engineers. During that time, we were learning the fundamentals of the industry and new technologies together. I a…
Contact
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Frequently Asked Questions
Common questions about my consulting services.
I offer project-based consulting, retainer advisory, architecture reviews, and workshops. The format depends on your needs—from a one-off assessment to ongoing support.