PCI DSS Expert

Two parallel workstreams: (1) Tech Due Diligence for acquisitions and portfolio companies. (2) AI strategy certification and AI governance consulting.

• Tech assessments for PE/VC acquisitions: code reviews, architecture analysis, scalability assessment
• Tech assessment frameworks and integration roadmaps for portfolio companies
• TÜV SÜD certification program: AI governance, EU Artificial Intelligence Act (EU AI Act)
• Strategic AI roadmap development for mid-sized companies

Results:

• Delivered several tech DD reports for investment decisions
• Developed integration roadmaps for portfolio companies
• TÜV SÜD “AI Strategy & Application Expert” (expected 31.12.2026)

• Completed the integration of log sources into Microsoft Sentinel, including GCP workloads – centralized consolidation of all security-relevant events from Azure and GCP environments for complete end-to-end telemetry and comprehensive compliance evidence
• Developed custom rules and use cases based on the GFG Use-Case Library and the MITRE ATT&CK Matrix to cover company-specific threats and GFG-relevant scenarios with precise, mapped detection rules
• Tuned detection rules to minimize false positives, optimized detection thresholds, and modeled exceptions – enabling the SOC to work with relevant, prioritized alerts while reducing Mean Time to Detect/Respond
• Built SOAR capabilities in Sentinel by developing playbooks to automate recurring response processes such as containment, user and host isolation, and ticketing – shorter response times and 24/7 scalability
• Designed and built a log transformation solution to normalize and enrich incoming raw logs (GeoIP, CMDB, threat intelligence) and convert them into a consistent schema for high-performance KQL queries, use case logic, and correlations
• Managed Azure security through Azure Policies to enforce security and compliance standards, prevent drift, and continuously remediate deviations
• Operated the Defender XDR portal to link endpoint, identity, email, and SaaS signals with Sentinel findings, enable holistic incident triage, and orchestrate measures directly from XDR

Technologies: Microsoft Sentinel, Microsoft Defender XDR, Azure Policy, KQL, GCP, MITRE ATT&CK

• Built and scaled a 35-member engineering team (Core Engineering, QA, and SRE) in 12 months, accelerating Midnight’s blockchain development on Parity’s Substrate framework.
• Defined strategic direction and aligned technology development with business objectives as a key member of the leadership.
• Optimized software development processes and implemented agile methodologies, enhancing operational efficiency and code security.
• Delivered projects in a fast-paced startup environment through effective project management and resource allocation.

• Objective/Motivation: PAYONE urgently needs a 360° view of its customers. So far, PAYONE has had no company-wide master data strategy. It is not possible to identify customers across all relevant systems.

The organization is to be enabled to identify customers across all relevant systems. Establishing the basis for master data management at PAYONE

• Challenge: Due to company acquisitions, the system landscape is very heterogeneous. The company is highly dynamic and burdened with many system harmonization and integration projects, meaning that resource bottlenecks and changes in project priorities repeatedly create an almost impossible task.

Due to BaFin findings, the project has a central task and role. The first focus is the migration of all customers, including their AML/KYC data, from the master data backend systems to Salesforce. This is intended to resolve one of the largest findings and establish the corresponding ODD/EDD processes.

In addition, customer data must be harmonized in Salesforce. Previous migrations resulted in duplicate customer records in some cases. The aim is therefore to maintain only one customer in Salesforce and, using the relevant information from the backend systems, also be able to identify which products the customer uses and in which processing systems the customer obtains PAYONE services.

Project: ONE Customer

Budget: €1.5 million

Team: 10/30 employees (full-time/part-time); 4 vendors/providers

Integration: 8 (subsystems/interfaces)

Applications: Salesforce; SAP S4/HANA; in-house developments

Tools: MS Office; Jira, Confluence, SharePoint

Methods: Hands-on; Agile (SAFe); Prince2

• Led discovery phase and POC for Shopware to Shopify Plus migration across EMEA markets, evaluating platform suitability, technical architecture, and multi-brand/multi-country capabilities against business requirements.
• Designed reference architecture for Shopify Plus implementation incorporating headless front-end patterns (Vue.js, Nuxt.js), CMS integration (Magnolia), and Azure middleware (APIM, Functions, Logic Apps, Service Bus) for 11 EMEA markets.
• Defined migration strategy analyzing data mapping, cutover approach, and zero-downtime deployment patterns using Varnish caching, GitOps pipelines, and CI/CD orchestration across six vendor teams.
• Architected multi-tenant Shopify Plus governance model with centralized admin, localized storefront customization, and compliance controls (GDPR, data residency).
• Prototyped AI-driven search optimization (LLM.txt, JSON-LD) for product discoverability in Google AI results, demonstrating post-launch performance opportunities.
• Defined EMEA expansion roadmap for 15+ markets through C-level strategic workshops, identifying phased rollout, market-specific configurations, and resource requirements.
• Tech Stack: React, Nuxt.js, Vue.js, Magnolia CMS, Shopware, Shopify Plus, Azure (APIM, Functions, Logic Apps, Service Bus, Front Door), Varnish, SAP, MS Dynamics, Docker, Kubernetes, GitHub Actions, PostgreSQL, Kafka

CRM and revenue platform managing billing and subscription workflows.

• Scaled payments infrastructure across data products, direct debit expansion and automated abuse prevention, generating $416K in annualized operational savings ($8K/week) by eliminating redundant gateway calls.
• Owned backlog and sprint execution for autonomous checkout abuse detection pipelines, designing real-time risk guardrails and velocity heuristics that blocked card testing attacks.
• Architected enterprise billing migrator user stories and data reconciliation mechanisms, achieving zero-downtime subscription state transitions and cutting $60K in infrastructure overhead.
• Expanded European direct debit (SEPA) payment capabilities, managing cross-squad API dependencies and automated webhook error-handling to eliminate checkout friction.

As a Council Member at GLG (Gerson Lehrman Group), the world’s leading expert network, I provide organizations, investment firms, and consulting companies with expert discussions on demand – wherever specialized knowledge in information security, IT governance, and regulatory compliance is needed.

My assessments are based on many years of practical experience in highly regulated industries: from building and implementing information security management systems (ISMS according to ISO 27001), IT risk and vulnerability management, and business continuity (ISO 22301) to the practical implementation of European regulations such as DORA, NIS2, BAIT, and the Cyber Resilience Act (CRA).

The cooperation is project- and discussion-based. I provide decision-makers with a practical perspective gained from real-world experience on cyber risks, security governance, and operational resilience – exactly when it is needed.

Unified ITSM framework

• Definition of a company-wide ITSM target picture
• Introduction of a uniform service structure across all business units

SLA and OLA management

• Building a standardized SLA framework
• Definition of service classes (Business Critical, Standard, Low Priority)
• Introduction of OLAs between internal teams
• Building meaningful SLA reporting
• Definition of KPI and service dashboards for business units

Service portfolio management

• Definition of service descriptions
• If needed, preparing possible cost and service billing

Ticketing & processes

• Incident management
• Uniform ticket categories
• Standardized prioritization
• Escalation matrix
• Automations
• Self-service optimization

Request fulfillment

• Service catalog across all business units
• Approval workflows

Problem management

• Introduction of root cause analysis
• Known error database
• Problem review process

Complete asset management concept

• Hardware lifecycle management
• Software lifecycle management
• Leasing lifecycle
• Mobile device lifecycle
• Monitor lifecycle
• Phone lifecycle

Processes

• Procurement
• Goods receipt
• Inventory
• Assignment
• Return
• Disposal
• Leasing return Goal: single source of truth for all assets

CMDB design

• Definition of all configuration items:
• Workplace
• Notebooks
• Monitors
• Mobile phones
• Printers

Infrastructure

• Servers
• Firewalls
• Switches
• WLAN
• Storage
• Backup systems

Cloud

• Azure resources
• Microsoft 365
• SaaS services

Relationships

• User ↔ Asset
• Asset ↔ Service
• Service ↔ Infrastructure
• Location ↔ Asset
• Goal: make all service dependencies visible

Software asset & license management

• License management concept
• License balancing
• Compliance reporting
• Microsoft license management
• Adobe license management
• SaaS management
• Contract management
• Renewal management

Interfaces & automation Existing systems

• Workday
• Joiner
• Mover
• Leaver

TESMA

• Leasing data
• Contract data

Matrix42

• Asset synchronization
• User synchronization

Active Directory / Entra ID

• User management

Microsoft 365

• License assignment
• Group management

Dormakaba

• Access processes

• Lifecycle services

Monitoring platforms

• PRTG
• Palo Alto
• Cisco

Reporting & KPI framework

• Definition of a management dashboard
• KPIs
• Ticket volume
• SLA fulfillment
• MTTR
• First resolution rate
• Asset accuracy
• License compliance
• Change success rate
• Service availability
• Degree of automation

Network redesign support

• Governance
• Support of the network redesign from an ITSM point of view
• Definition of affected services
• Change management structure
• Communication concept

CMDB integration

• Recording of all network components
• Service mapping
• Dependency analysis

Validation of documentation and knowledge base articles

• Network documentation
• Operations documentation
• Standard changes

Monitoring & event management

• Target picture
• Central monitoring concept
• Event management process
• Alerting strategy
• Escalation model

Systems

• Cisco

• Palo Alto

• Fortinet

• Rubrik

• Veeam

• Matrix42

• Azure

• Microsoft 365 Automation

• Ticket creation from monitoring

• Escalations

• Standard actions

Audit, compliance & information security

• ISO 27001 consulting
• TISAX consulting
• NIS2 preparation - consulting
• Audit-ready processes
• Documentation structure
• Evidence tracking in Matrix42

Roadmap

• 12-month roadmap
• Prioritization of all measures
• Quick wins
• Medium-term projects
• Long-term target picture
• Documentation

• Lead Product Owner role for the BFSG pilot journey “Search and Book” across web and app, focusing on digital accessibility, UX, conversion, and regulatory implementation.
• Created and prioritized the product backlog; derived user stories and acceptance criteria from legal standards (BFSG, WCAG 2.1)
• Developed a product vision that combines digital accessibility, user-centered UX, and conversion optimization for the booking journey
• Cross-stream release management and quality assurance across the entire web and app area, including go/no-go decisions, rollout, and user acceptance tests
• Coordinated and prioritized with Legal, Compliance, external BFSG consultants, UX, Development, Marketing, and Management
• Conducted user research as well as usability and accessibility tests (including screen readers and keyboard navigation) and prototyping with UX/UI
• Defined KPIs to measure accessibility, conversion, and user guidance
• BFSG pilot journey “Search and Book” successfully delivered: first accessible features rolled out and the foundation for a long-term BFSG-compliant booking journey established
• Established sustainable process integration through close collaboration with consulting partners and internal teams

In my role as Senior Cloud DevOps Architect for BP, an oil and gas company, I had the mission to migrate the Electric Vehicle Charging platform of the EV Division from on-premises and Azure to AWS cloud, resulting in a hybrid multi-cloud, multi-tenant SaaS solution.

Deployment with Kubernetes for the application layer meant provisioning Kubernetes clusters managed by EKS and AKS, with a focus on integrating them into a multi-tenant environment. This integration was achieved by using Kubernetes namespaces and access controls to ensure data isolation and privacy enforcement.

In the database layer, we chose an RDS instance with PostgreSQL to support the backend infrastructure of our applications. Tenants shared the same RDS instance, but each had a dedicated schema.

To ingest near real-time data from physical charge points (CPOs), as IoT devices, via the OCPI protocol, we ran into significant delays with batch processing. As a result, we built a real-time streaming data pipeline using Apache Kafka, while prioritizing an event-driven architecture.

Led collaboration across multiple internal teams, external vendors, cloud providers, and on-site partners to integrate over five systems into a unified solution.

Achievements:

• Successfully designed and implemented hybrid multi-cloud solutions, integrating multiple cloud platforms (AWS, Azure) with on-premises infrastructure, using Site-to-Site VPNs, Firewalls, and Load Balancing.
• Led the migration of on-premises infrastructure to multi-cloud, multi-tenant infrastructure, resulting in 30% faster processing times.
• Migrated workloads from VMware and Hyper-V environments to cloud-based VMs, leveraging cloud-native services to optimize performance, cost efficiency, and scalability.
• Designed a multi-tenant Kubernetes platform leveraging the Kubernetes ecosystem, using Karpenter for dynamic EC2 node provisioning, KEDA for event-driven pod autoscaling (e.g., Kafka message lag), and Rancher for centralized monitoring of multiple clusters (EKS, AKS, or on-prem K8s), replacing Microsoft-centric Azure Arc management service.
• Designed and implemented Python-based FastAPI microservices as part of the EV core-backend on AWS EKS application layer, powering data ingestion and customer analytics pipelines.
• Developed asynchronous, event-driven APIs (Python-FastAPI) for real-time integration with CPOs, supporting OCPI 2.3 and OICP protocols.
• Designed and implemented a secure, production-grade Azure Databricks platform using Terraform, ensuring scalability and cost efficiency.
• Migrated on-premises ERP to a hybrid Dynamics 365 architecture with ERP hosted locally and CRM running in Azure, integrated via Azure Arc.
• Automated CI/CD pipelines for Databricks notebooks and jobs using GitHub Actions & Databricks CLI, reducing deployment time. Reduced infrastructure provisioning time by 70% by automating cloud resource deployment with GitOps.
• Ensured compliance with internal audit and data governance standards (GDPR) through OAuth2/OIDC-based authentication and fine-grained role-based access controls.
• Developed a Zero Trust security model, enforcing least-privilege access and microsegmentation, enhancing security posture and compliance with GDPR and NIST.
• Built interactive analytics dashboards in Amazon QuickSight, integrating data from S3 and Redshift to deliver real-time business insights and visualizations with embedded access for multi-tenant users.
• Led cloud security assessments and full-lifecycle cybersecurity integration during M&A, covering AWS, Azure, IAM (Entra ID), and data protection, while aligning security posture with NIST, ISO 27001, and GDPR across hybrid and cloud-native environments.
• Reduced cloud costs by 64% for a client's dev environment by implementing automated start/stop schedules for EC2 and RDS instances via AWS CDK with EventBridge Scheduler or AWS Systems Manager.

Tech stack:

• Infrastructure as Code: Terraform, AWS CDK, Ansible.
• Containers: Kubernetes on EKS, AKS, Docker.
• Streaming Data Processing: Kafka to Confluent Cloud, after AWS MSK.
• Frontend: TypeScript, React, NextJS, Hooks, Styled Components.
• Backend: Python with FastAPI, also Node.js with NestJS.
• Database: Aurora on PostgreSQL with TypeORM, RDS on SQL Server, Azure Databricks full setup and administration, ETL Pipelines.
• CI/CD and GitOps: GitHub Actions, Azure DevOps, ArgoCD.
• Monitoring and Observability: Prometheus and Grafana.
• Virtualization: Hyper-V, VMware Cloud on AWS, Azure Migrate.
• ERP Systems: Odoo, Microsoft Dynamics 365 Business Central on Azure, integrated with Azure Arc.
• Networking: Site-to-Site VPNs, AWS Direct Connect, Azure ExpressRoute, Firewalls (AWS Network Firewall, Azure Firewall).
• Security: IAM, NIST Framework, Zero Trust Security, AWS WAF, AWS Shield, GuardDuty.

• PRISMA project
• Ansible automation
• Windows third-level support for Windows NT, Windows 2000, Windows 2013, Windows 2016, Windows 2019

• It is like a startup within REWE, where we have to build a new forecasting system on Google Cloud Platform from the scratch. Although, officially my role is called MLOps, my actual tasks also include development of data processing pipelines (data engineering) and data scientists tasks such as feature engineering and model trainings.
• GCP: Terraform (tofu), Vertex AI (Kubeflow), Cloud Run, IAM, Google Cloud Storage, BigQuery, Artifact Registry
• Data engineering: Snowflake as the main data warehouse, Terraform, DBT for data model implementations
• CI/CD: GitLab. We have built a CI/CD pipeline that automates deployments of new releases up to production environment
• Development of feature store and data synchronization between environments
• Data science: evaluation of different forecasting models, including CatBoost, Contextual Gamma and Random Forest; implementation of training pipelines using Kubeflow on Vertex AI; scaling and development of an event-driven interface using Kafka as a forecasting service; evaluation of MLFlow for model tracking and model registry
• Implementation of REST API using KeyCloak OAuth2 and OpenID (JWT)
• Monitoring: implementation of dashboards with Grafana, Prometheus, Mimir, Streamlit and Loki to monitor prediction metrics, GCP and Snowflake costs for pipelines, and system metrics
• Development of Copilot Agent Skills

• Technical lead for CI/CD modernization in the "Group Archive 4.0" system
• Architecture and steering responsibility according to the statement of work
• Setting up modern build and deployment processes
• CI/CD coaching and enablement of the internal development team
• Integration of modern DevOps, security, and compliance standards
• Ensuring technical governance, including collaboration with internal audit and BaFin
• Independently executing the modernization measures
• Supporting the team in adopting new technologies and methods

• The customer is undergoing a comprehensive transformation. All SAP ECC landscapes worldwide are being migrated to SAP S/4HANA, with the goal of introducing a standard template worldwide.

• The program also includes the “RISE with SAP” migration and modernization program, which may involve migrating the landscapes of selected country installations to the SAP Private Cloud.

• On the stakeholder side, the program reporting line extends to the company’s executive board and that of the implementation partner.

• Fiserv Germany’s ERP landscape currently includes several non-standard SAP tools and applications that extend the functionality of the ECC environment and can often be integrated into downstream systems. As part of the transition to SAP S/4HANA, it is essential to assess the core functionality, integration points and future viability of these applications in order to determine their alignment with the target architecture.

• The focus of the work is on providing expert advice and assessment to define the scope, strategy and roadmap for transitioning Fiserv Germany’s SAP ECC system to SAP S/4HANA.

• The recommended best practices from SAP are followed and a structured approach is used to ensure a smooth transition with minimal disruption while maximizing business value.

• This assessment forms the basis for a successful SAP S/4HANA transformation and ensures alignment with industry best practices, regulatory compliance and future scalability.

• Migration Strategy Definition – assessment of available transition approaches based on business objectives, technical feasibility and SAP Best Practices.

• Technical Readiness Assessment – conducting a system analysis to assess compatibility, custom code impact, data volume management, integration points and infrastructure readiness for SAP S/4HANA.

• Business Process Impact Analysis – reviewing the latest business process documentation to define the scope and effort required to implement the necessary functions in SAP S/4HANA and to identify opportunities for process optimization.

• Roadmap for Non-SAP Systems and Applications – assessment of third-party and legacy applications regarding their integration with SAP S/4HANA and recommendation of consolidation, migration or replacement strategies.

• Deployment & Implementation Planning – defining a phased approach for implementation, including project schedules, risk mitigation strategies and key milestones aligned with business priorities.

• This transformation takes place in phases: the Discovery phase leads to the Explore phase, which is followed by the Design phase and finally implementation.

• Program management

• Change management

• Requirements management

• Transition management

• Stakeholder management

• Risk management

• Comprehensive coordination