Hello, I’m Marcel Berger

💻 Senior Software Architect, Cloud Engineer & Digitalization Expert – with 20 years of deeply rooted IT expertise Java Mastermind • Quarkus Pioneer • Flutter Expert • DevOps Guru • IT Strategist with Hands-on Mentality

I’m not a showman. I’m straightforward in the Hanseatic way – born and raised in Osnabrück, with a clear edge, technical depth, and a solution-oriented mindset. If you’re looking for someone who talks instead of delivers, you’re in the wrong place. But if you need someone who pragmatically implements digital projects, takes responsibility, and isn’t afraid of complexity – then welcome.

My story begins sometime in 1989 or 1990 – nobody knows exactly anymore. Facebook hadn’t been invented yet, film for cameras was expensive, and if you wanted to capture memories, you needed either a good camera or a damn good memory. But the ENERGY STAR logo already existed – and I had my first computer: a Weico Computer running Weico DOS. BASIC was my first language – long before I mastered German grammar. Pascal, C, Java, Python followed – and a career that took me through many worlds: from the shell to the cloud, from startups to corporations, from the terminal to the boardroom. I grew up in a world where you still configured the BIOS manually, Stack Overflows couldn’t be googled, and you learned to manage memory efficiently – experiences that shape me to this day.

I develop scalable enterprise backends with Java, automate workflows with Camunda BPMN, bring complex systems to the cloud (Azure, Kubernetes, Civo), and develop native mobile apps with Flutter. I think long-term, with Nordic pragmatism, and develop with a clear goal: software that works. Today, tomorrow, the day after.

Besides my passion for software, I worked for many years in the hospitality industry on cruise ships and in upscale hotels. I’ve opened bars, led teams, planned events, and delighted international guests. This time taught me: leadership is more than project planning, communication more than emails, resilience more than a buzzword. I combine the charm of a host with the analytical depth of an IT architect.

I studied Business Information Systems, trained as a restaurant specialist and bar master (IHK). Not just hard on the keyboard, but also hard at work. I’m a fan of electronic music and long nights – sometimes for programming, sometimes for partying. I find my balance between lines of code and beats. Structure, pragmatism, and solution-oriented action are always at the forefront for me.

I’m like North German weather: clear, straightforward, with depth. I analyze like a CTO, act like a captain in a storm – and always stay on course.

Anyone who googles me finds not just code, but concepts. Not just skills, but solutions. Not just projects, but results. Welcome to Marcel Berger – the architect behind performant, secure, and economically sensible IT. Real. Honest. Efficient.

My Profile in Keywords

🖥️ Technologies & Software Development

Over 20 years of experience in software development, more than a decade as software architect and technical lead in complex enterprise projects
Cloud-native backend development with Java (J2EE / Java EE, Spring Boot, Quarkus) – from classic enterprise systems to highly scalable microservices architectures
Flutter app development for iOS and Android: architecture, state management with Riverpod, responsive UI/UX, performance optimization, and integration of powerful REST and GraphQL APIs
Development of robust enterprise integrations and API designs for REST, GraphQL, and SOAP, including interface architecture and security concepts
Databases: PostgreSQL, Oracle, MySQL – modeling, optimization, and integration for high-performance applications
Event-Driven Architectures with Apache Kafka and RabbitMQ for scalable and resilient system communication

Security & Identity Management

Expert in security and identity management, including implementation of Keycloak, OAuth2, SAML, SailPoint IdentityIQ, and Microsoft Entra ID (Azure AD)
Design and implementation of secure authentication and authorization solutions, identity federation, and single sign-on for enterprise and cloud environments

DevOps, CI/CD & Cloud Operations

Building complete CI/CD pipelines and automation with GitHub Actions and Argo CD
Containerization with Docker and Podman, and orchestration with Kubernetes, including infrastructure-as-code and automated deployments in production cloud environments
Experience with Azure Cloud Services, especially AKS (Azure Kubernetes Service), Blob & File Storage, Key Vault, and other cloud-native components

Digital Transformation & Process Automation

Strategic driver of digital transformation: analysis, optimization, and digitalization of business processes in medium-sized companies and critical infrastructures
Implementation of sustainable process digitalization and workflow automation, including BPMN solutions with Camunda and low-code automation with Make.com and Zapier

Leadership, Agile Methods & Business

More than 10 years of experience as entrepreneur and self-employed, with founding, building, and leading multiple companies in IT consulting, software development, and digital business models
Entrepreneurial strategist focused on scaling, monetization, and developing sustainable digital products and business models
Team leadership and mentoring of developers, architects, and cross-functional teams in agile projects, as well as responsibility for recruiting, coaching, and team development
Practical experience with Scrum, Kanban, and DevOps-oriented development, including product ownership and stakeholder management at C-level

Current Position & Side Projects

Currently: Head of Digitalization & Project Coordination at a KRITIS infrastructure operator, responsible for digital strategy, IT project portfolios, cybersecurity, and innovation
Freelance: Entrepreneur, app developer, and content creator – conveying complex IT topics, building scalable digital business models, and developing market-ready apps with clear monetization strategy

Technologies & Tools – my daily toolkit

Category	Technologies & Platforms
Programming Languages	Java (J2EE / Java EE, Spring Boot, Quarkus) • Dart • Python • Bash (Shell) • C • BASIC • Turbo Pascal • JavaScript • TypeScript • Go • Groovy • Swift
Backend Development	Quarkus • Spring Boot • Java EE • RESTful Services • GraphQL APIs • Microservices Architectures
Frontend & UI Frameworks	Flutter (iOS & Android) • Vaadin • Angular • Vue.js • SwiftUI (iOS) • JSP • JSF • PrimeFaces • RichFaces
Identity & Security	Keycloak (IAM) • OAuth2 • SAML • JWT • SailPoint IdentityIQ • Microsoft Entra ID
DevOps & CI/CD	Git (GitHub, Bitbucket) • GitHub Actions (CI/CD Automation) • Jenkins • Argo CD (GitOps Deployment) • Docker • Podman • Kubernetes • K9s (Kubernetes Management) • Portainer
Build & Repository Management	Maven • Gradle • Nexus Repository • Sonatype Nexus • JFrog Artifactory • SonarQube • SonarCloud
Workflow & Process Automation	Camunda BPMN • Kogito • External Task Pattern • Make.com (Low-Code Automation) • Zapier (Integration Automation)
Cloud & Infrastructure	Microsoft Azure (AKS, Entra ID, Key Vault, Blob & File Storage) • Civo Kubernetes
Operating Systems & Administration	Windows • macOS • Linux (Ubuntu, CentOS, RedHat, Debian, Alpine Linux, Raspberry Pi OS)
Event-Driven Architecture & Messaging	Apache Kafka • RabbitMQ
Databases & Storage	PostgreSQL • Oracle DB • MySQL • H2 Databases • MongoDB • Cassandra • Liquibase (Database Migrations)
Testing & Quality Assurance	jUnit • Mockito • Selenium
Reporting & Template Engines	JasperReports • Qute (Quarkus Template Engine) • Thymeleaf • Freemarker • Velocity
IDE & Development Environments	Eclipse • JetBrains IntelliJ IDEA • JetBrains DataGrip • Android Studio • Xcode • Visual Studio Code (VS Code) • Vim • Nano
Business Tools & Office	Word • Excel • PowerPoint • Miro • Jira & Confluence • SAP
Methods & Work Practices	Scrum • Scrum Master Certified • Scrum Developer • Kanban • Pair Programming • Test Driven Development (TDD)

Professional Background

I’ve been developing enterprise software long before “digitalization” became a buzzword in boardrooms. Whether regulatory financial systems with the highest security requirements, process platforms in the energy sector, complex identity management solutions, or AI-powered document analysis – I deliver IT solutions that work. Robust, scalable, understandable.

For me, IT is not an end in itself, but a strategic tool. I don’t think in features, but in real business value. My systems are designed to be productive tomorrow, extensible the day after, and still maintainable and cost-effective in five years. I make architecture decisions based on facts – focusing on clean code, maintainability, scalability, security, and operating costs throughout the entire lifecycle.

Currently, I lead digitalization and project coordination in a company of critical infrastructure (KRITIS). There I am responsible for the digital strategy, develop process digitalization, automation solutions, and secure cloud architectures, lead my team professionally and organizationally, and manage complex projects with high visibility up to the executive level.

Before that, I was an entrepreneur and managing director of my own software company for over ten years. During this time, I:

Managed several million-euro projects – from acquisition through architecture and implementation to operations
Built and led cross-functional teams consisting of developers, architects, DevOps engineers, and UI/UX designers
Developed APIs and microservices architectures that are now productively used in financial institutions, industry, and the energy sector
Established governance, security, and compliance structures to meet regulatory requirements securely and verifiably
Built CI/CD pipelines, containerization, and automated deployments to significantly reduce time-to-market and operating costs
Created technical documentation, architectural decisions, and operational concepts that were as understandable for stakeholders as they were precise for developers

I can plan, architect, develop, operate – and explain software. Understandably. Responsibly. Reliably. I combine technical depth with strategic thinking, speak the language of developers and decision-makers, and always keep the big picture in mind: business value, quality, security, and sustainable IT architectures.

One Company. Two Minds. Infinite Possibilities.

Berger & Rosenstock GbR combines the bundled expertise of Jasmin Rosenstock and Marcel Berger under one strong brand.
What once began as simple collaboration is now a dynamic symbiosis of technology, business, beauty, and lifestyle – supported by solid education, practical experience, and entrepreneurial passion.

Jasmin Rosenstock

Jasmin Rosenstock holds a Bachelor’s degree in Health Promotion from Coastal Carolina University (USA) and a Master of Arts in Public Relations and Corporate Communications from the University of Europe for Applied Sciences.
She brings comprehensive knowledge in health promotion, corporate communication, brand development, and PR strategy. Her focus areas are beauty, lifestyle, communication, and brand positioning, combining academic expertise with creative content creation and strategic thinking.

Marcel Berger

Marcel Berger holds a Bachelor’s degree in Business Information Systems from the Technische Hochschule Mittelhessen and combines technical competence with business know-how.
He is also a trained restaurant specialist (IHK), bar master (IHK) with additional training as bartender and comprehensive knowledge in gastronomy management, barista with a focus on coffee preparation and sensory analysis, and IHK-certified trainer (AEVO).

He has more than two decades of experience in IT, starting from programming and software architecture through process digitalization and automation to managing companies with millions in revenue. His profile combines deep technical expertise with entrepreneurial thinking, leadership, and pragmatic implementation skills.

Our Common Focus

Together we develop digital products such as apps, automation solutions, and workflows, build strong brands in e-commerce, and produce professional content for YouTube and social media.
We combine technical knowledge, entrepreneurial thinking, creativity, and communication strength – for results that are visible, usable, and profitable.

Whether software architecture, print-on-demand products, beauty and styling tips, brand building, or content with a clear attitude:
As an entrepreneurial couple, we work practically, directly, and always with a clear focus on added value, impact, and sustainable success.

Contact & Presence

Marcel Berger – IT, Software & Business

Jasmin Rosenstock – Beauty & Lifestyle

Our Brand

Online Shop: novinophobia.store

Our Company

GbR Website: berger-rosenstock.de

“The only way to do great work is to love what you do.” – Steve Jobs

Thank you for your visit. If you’re looking for real substance in the IT world – you’ve just found it. Honest. Direct. Nordic good.

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Marcel R. G. Berger

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