Debian Experts in Cologne

• Project: ESU Windows and SQL Server consolidation / Configuration Management in ServiceNow
• Creation of an as-is analysis of all servers worldwide
• Creation of an as-is analysis of all SQL servers worldwide
• Creation of requirements analyses for SQL and server migrations
• Coordination of requirements with partners for migrations to Hyper-V (on-premises) or Azure Cloud
• Moderation of jour fixe meetings
• Creation of roadmaps and solution models for server migrations
• Setup of test scenarios
• Moderation of workshops for the introduction of a Global Admin Team
• Creation of data models (CMDB) in ServiceNow
• Conducting workshops for the CMDB data model
• Creation of solution models for the CMDB
• Creation of seamless configuration and work documentation for the CMDB
• Creation of reports for license management
• Creation of KPIs for data quality in ServiceNow
• Creation of a service catalog
• Moderation of workshops for creating service requests
• Interface between needs analysis and ServiceNow development team
• Systems used: Windows 7, Windows 10, Microsoft Office 365/2010, Windows Server 20xx, SQL Server 20xx, SharePoint, Azure Cloud, Hyper-V, ServiceNow, various tools

• Business analysis
• Requirements management
• Project management
• Stakeholder management
• Team leadership

• Evolved the platform from bare-metal infrastructure with a monolithic PHP application to a hybrid Google Cloud architecture with Go microservices on Kubernetes
• Managed and scaled a production infrastructure with 300+ VMs and dozens of clusters, including MySQL, PostgreSQL, MongoDB, RabbitMQ, Redis and Elasticsearch clusters
• Designed architecture, deployment, monitoring, performance analysis, and upgrades for all platform services using Terraform and Ansible
• Migrated observability systems from ELK and Prometheus to Datadog, managed with Terraform
• Introduced Jenkins CI/CD with SonarQube integration and automated tests to speed up feedback cycles
• Containerized the testing environment and implemented GitLab CI pipelines for Docker image builds, static code analysis, and infrastructure tests
• Performed zero-downtime migrations of MySQL and MongoDB clusters to Google Cloud
• Developed reusable Ansible roles for database clusters and automated data obfuscation for staging environments
• Decomposed monolithic databases and migrated to microservice architectures
• Built tools to detect and optimize slow queries in MySQL and MongoDB
• Conducted online schema migrations with pt-online-schema-change without downtime windows
• Developed internal Go applications for batch queries, GitLab-Jira integration, and MongoDB backup recovery
• Technologies: Debian, Ubuntu, Alpine, Go, Bash, Python, PHP, SQL, GitLab CI, Jenkins, Drone CI, MySQL, MongoDB, PostgreSQL, Redis, Elasticsearch, RabbitMQ, Kafka, Docker, Kubernetes, Nomad, Ansible, Terraform, Grafana, ELK, Prometheus, Datadog, Nagios, Zabbix, Nginx, HAProxy, Vault, Helm, SonarQube, Filebeat, Auditbeat, Google Cloud, AWS

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

• Hybrid role as the first software engineer in the company to bootstrap the organization, laying out technical foundation and advising management on organizational aspects.
• Set up the SaaS platform architecture, selected languages and tools, and designed processes to deliver customer value quickly and reliably.
• Designed and implemented build and continuous deployment pipeline with multi-tenant approach enabling extreme scaling of the SaaS platform.
• Established initial ITSM and support processes, provided monitoring and alarming, and participated in the on-call team.
• Proposed new approaches to scale the platform and improve backend interfaces to mitigate bugs and communication overhead.
• Mentored new employees and served as a trustful team member and lateral leader.
• Conducted interviews for technical roles.
• Used technologies: Typescript, Node.js, Bash, Google Cloud Platform (App Engine, Cloud Run, Cloud Functions, Google Endpoints, Firebase), GitHub Actions, Docker, Terraform, MongoDB, Firebase, REST APIs, GraphQL.

• Developed a SCIM-compliant Python interface to connect external systems
• Expanded and enhanced UCS modules in Python
• Extended and newly developed Helm charts for container orchestration in Kubernetes
• Maintained and further developed CI/CD pipelines in GitLab
• Implemented automated tests with Pytest and Playwright

'Nubus' is based on a microservice architecture, relies on open source technologies, and runs in Docker containers.

UCS is an IAM complete solution based on Debian, used as an alternative to Microsoft's Active Directory. The work was characterized by the close integration of infrastructure and application logic.

• TSI customer project data center migration (since 2024-07-01)

• Inventory of active IT/OT components

• Creation and management of the migration concept

• Planning and execution of migration tests

• Carrying out the IoT migration (network, VPN gateway, firewall adjustments)

• Service migrations (mobile services)

• Re-design of outdated technologies/services

• Integration into operations

• Logistics bus project at Daimler Truck and Mercedes Benz (2024-01-01 – 2024-06-30)

• Development manager/technical consultant for the logistics bus

• Coaching customers/TSI development teams and product owners

• Creation/review of architecture designs and documentation

• Project planning/customer meetings

• Support for migrations from Java/WebSphere/JBoss to Kubernetes

• Service design for performance visibility (2022-06-01 – 2023-10-31)

• Performance visibility service development, network monitoring service for Telekom internal customers

• Planning/integration/expansion of PV monitoring in cloud environments (AWS, Microsoft Azure)

• Design/planning/implementation of performance visibility services based on NetScout/Kadiska software in customer environments

• Agile project management/execution of PoCs (proof of concepts)

• Design/architecture/concept creation

• Diagnosis of network issues

• Packet capturing/debugging

• Preparation of customer and training documentation

• Developing and implementing IT architectures for business-critical applications, BCM/ITSCM, SAP, BTP and S/4HANA, Azure, interfaces and IT infrastructure according to Uniper security guidelines and compliance policies

• IT cloud infrastructure management: Requirements management and SLA definition for critical SAP and non-SAP applications and infrastructures based on the Key Production Environment algorithm; creating a conceptual target architecture; creating agile project plans for migration; risk management and vulnerability analysis; developing training content and e-learnings; establishing and optimizing risk management processes; creating action catalogs, architectures and ITSCM/emergency plans; identifying and managing internal and external partners

• Developing BCM/ITSCM concepts and IT infrastructure architectures for business-critical applications according to Azure Cloud, SAP BTP and Uniper governance frameworks; documenting and implementing ITSCM/emergency plans in line with disaster recovery patterns; creating training materials and coordinating training sessions; testing, simulating and optimizing BCM/ITSCM plans and IT architectures; ongoing training of management and staff on IT architectures, operating models, SAP BTP as well as BCM and emergency plans

• Technical lead of the SAP services team: Managing and coordinating external vendors, service owners and application managers; developing and implementing ITSM processes (incident, problem, change, SLM, IT security, provider management, ITSCM, asset and configuration management); training internal and external service providers and service managers; optimizing IT service contracts and OLAs; updating the service catalog; communicating and escalating issues; defining responsibilities and monitoring SLA criteria; conducting root cause analysis; partly acting as release manager for SAP ERP releases

• Migration: Requirements management, budget and financial planning; risk management; defining and implementing transformation and migration plans; weekly reporting to Uniper vice presidents and senior management; maintaining project plans and backlogs in Jira and Azure DevOps; managing up to 50 internal and external stakeholders; workshops and meetings; quality assurance: defining quality gateways and monitoring

• Test management: Creating and documenting test plans; evaluating test risks; identifying stakeholders for test plans; documenting test scenarios; defining error categories and quality gateways; coordinating and executing tests