Full Stack Developer @ DBH Logistics IT AG | Hamburg, Germany

I build solutions to real-world problems that bring real value to the table. My focus is on clean architecture, comprehensive testing, and production-ready applications — currently working on modernizing enterprise logistics and customs software.

• 🏢 Full Stack Developer at DBH Logistics IT AG — working on Java legacy modernization and React/TypeScript frontends in the customs & logistics domain
• 🔭 Previously built a SaaS product with 2,000+ users and went through 3 YC application cycles
• 🌱 Currently deepening: Java internals & enterprise patterns, Spring Boot, domain-driven design in logistics
• 💡 Passionate about clean systems, real automation, and bridging technical implementation with business value
• 🎓 B.Sc. E-Commerce, FH Wedel · IT-Assistent Softwareentwicklung, PTL Wedel
• 📍 Hamburg, Germany

Backend & Frameworks

Frontend

Databases & Search

Data & Automation

Testing & Quality

DevOps & Tools

Tech: Spring Boot, PostgreSQL, Keycloak, Next.js, OpenRouter AI

A full-stack flashcard application with AI-powered card generation and a three-tier difficulty system.

Key Features:

• 🧪 Comprehensive testing with Testcontainers, Mockito, and MockMvc
• 🔐 JWT/OAuth2 authentication via Keycloak
• 🤖 AI integration for automated flashcard generation
• 📊 Clean architecture with proper separation of concerns

📺 Watch Demo | 📖 Read Docs

Tech: Spring Boot, Elasticsearch, Keycloak, Docker, Railway

A backend-focused platform for gym reviews with full-text search and geo-location queries.

Key Features:

• 🔍 Elasticsearch for full-text & geo-radius search
• 🚀 Deployed on Railway with Docker containerization
• 🔐 OAuth2 Resource Server with Keycloak integration
• 📸 Secure file upload system with path-traversal protection

📺 Watch Demo | 📖 Read Docs

🧪 Testing Culture Unlike many juniors, I prioritize testing from day one. My projects feature production-parity testing with Testcontainers, comprehensive unit tests with Mockito, and integration tests with MockMvc.

🚀 Real Production Experience I don't build localhost demos. My applications run on cloud platforms with proper security (OAuth2/JWT), containerization (Docker), and real-world features. Before joining DBH, I co-built a SaaS product that reached 2,000+ users.

🔄 Legacy to Modern At DBH I work daily on Java legacy modernization — understanding and migrating production-grade enterprise code is a different skill set than greenfield development, and one most juniors haven't touched.

💼 Business + Technical Mindset With an E-Commerce background, I understand both technical implementation and business value. I can bridge the gap between developers and stakeholders — and I've applied that in real startup and enterprise contexts.

📍 Hamburg, Germany

class Jo extends Developer {

    String currentRole     = "Full Stack Developer @ DBH Logistics IT AG";
    String domain          = "Customs & Logistics Software";
    String[] dailyStack    = { "Java 8→21", "Spring Boot", "React", "TypeScript", "Tailwind" };
    String[] deepening     = { "Java Internals", "Enterprise Patterns", "DDD", "Spring Security" };

    @Override
    public void work() {
        while (motivated) {
            modernizeLegacyCode();
            buildCleanFrontends();
            writeTests();
            shipToProduction();
        }
    }
}