Oracle Database Experts in Cologne

• Further development of the existing e-commerce platform based on SAP Commerce (Hybris) to meet the growing demands of digital commerce.
• Ensuring the scalability and performance of the backend, so the platform remained stable and efficient even under heavy user load.
• Development and integration of new OCC REST APIs and services for modular extensions and flexible adjustments, to implement new features quickly.
• Optimization of data flows and interfaces, which significantly improved platform efficiency and system performance.
• Ensuring a maintainable and scalable code base by using Clean Code principles, proven design patterns, and a future-proof architecture.
• Reduction of errors through extensive testing with JUnit, Mockito, and load tests with Gatling, supported by the introduction of automated test processes.
• Improved system performance through targeted refactoring measures and efficient database queries, especially to handle peak loads.
• Use of modern cloud and monitoring tools such as Kubernetes, Google Cloud Platform (GCP), and Grafana to ensure a stable and monitored infrastructure.
• Clear improvement in efficiency, scalability, and reliability of the platform, which now meets the demands of a dynamic and growing e-commerce market.

With project PRIZMA, DB will modernize its infrastructure on the one hand, and develop a fail-safe IT landscape on the other hand, which can be restored quickly and securely in case of a disaster.

• Capture current architectures of existing systems as well as methodical consulting and development of target architectures
• Deepen and maintain the building plan / target IT landscape
• Implement technical architecture concepts & architecture descriptions
• Implement migration concepts for updating and further developing the platform and information systems
• Assess submitted improvement suggestions as part of the project
• Capability management: identify capability gaps, develop target visions, and support transformation planning within the enterprise architecture.
• Create a compatibility matrix of the components in use and compare dependencies of specific versions
• Create an IT concept for extending the platform with the following topics: hardware and software requirements, security, licensing, high availability, load balancing, backup & recovery, update strategy, monitoring integration, etc.
• Coordinate with business architects as well as technical architects from the cross-functional architecture area of the PRISMA program for the topics (backup, Active Directory, monitoring, Citrix, and business applications ...)
• Status meetings and alignment of project planning with the Release Train Engineer / Project Manager
• Advise the Release Train Engineer / Project Manager in identifying project risks
• Advise the System Architect Engineers in steering the implementation of the concept
• Implement the IT concept
• Document the infrastructure

Label: MS Project, LINUX, Windows, ORACLE, Java, REST, SharePoint, Microsoft Exchange, UML, Enterprise Architect, BPMN, AZURE, AWS, V-MODEL, Micro Service, VisualStudio, SAP S/4HANA, SCRUM(SAFE), ESB (TIBCO), Python, Innovator, LeanIX (TOGAF), Ansible, Ansible Tower, Ansible Automation, ROBOT, SpringBoot

Successful delivery of projects on behalf of customers:

• -> 2023 – present: Project management for the consolidation of sites/data centers for a large telecommunications provider (infrastructure project, customer: Telefonica)

• Opening and preparing new sites

• Application migrations

• Decommissioning and handover of old sites

• -> 2021 – 2022: IT multi-project management for a large car leasing company (customer: Athlon)

• Migration of applications to the cloud and to another data center

• Additional projects to expand and optimize the application landscape

• -> 2021: Project management for the development of a platform providing internet access on aircraft operated by various airlines (customer: m3Connect/German Telekom)

• -> 2017-2020: Responsible management of an IP network consolidation (infrastructure project, customer: Cisco/Vodafone) at a large telecommunications provider

• Planning and coordination of migrations and their rollout

• Team leadership and integration of different teams (network operators, hardware and service providers)

• Planning and implementation of a migration strategy for master and transaction data for the continuous loading of a cloud-independent database
• Creation and pilot implementation of a company-wide Business Data Model for customers, suppliers, contracts, products, prices, consumption, invoices, and dunning
• Concept and consulting for a Data Governance Framework incl. definition of committees, roles, processes, and metadata model
• Operationalization of the Data Governance Framework with definition of data standards
• Sub-project management in two pilot projects (PoCs) for Data Governance systems (ErwinDIS and Atlan)
• Training and coaching the data team in migration, data quality, and data modeling

• 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

• Coordination and planning, execution, documentation, and analysis of test cases
• Development of test concepts considering best practices (e.g., test pyramid) with a focus on reliable, automatable test runs
• Implementation and maintenance of test cases according to the test concepts
• Technologies: Citrix Workspace, Shopify, Jira, Xray, MS Teams, MS SharePoint, Confluence, MS Office 365

PLANT-MY-TREE®-per-order

The application enables Shopify merchants to automatically place tree-planting orders for every incoming order. By integrating ecological contributions directly into the purchase process, the manual effort for tracking and billing reforestation initiatives is eliminated. The system increases transparency for end customers through real-time visualizations of the ecological impact directly in the storefront. The architecture is based on a modular monolith with Spring Boot in the backend and an integrated React app inside the Shopify admin area. The solution uses webhooks to capture order data in an event-driven way and integrates the weclapp ERP system for automated monthly invoicing. An app proxy mechanism provides dynamic statistics such as CO2 compensation and planted trees without any performance loss for the merchant shop.

Tasks:

• Design of the modular software architecture based on Spring Modulith to ensure high maintainability
• Development of the event-driven business logic for evaluating Shopify orders via webhooks
• Implementation of automated invoicing by connecting the weclapp REST API
• Building the frontend using React Router and Shopify App Bridge for native integration
• Design of the database model and implementation of the persistence layer with JPA/Hibernate and Prisma
• Integration of internationalization processes for global use in the frontend and email communication
• Automation of deployment processes using Docker and GitLab CI/CD

Project skills: Java 25, Spring Boot, Spring Security, Spring Modulith, Hibernate, JPA, REST API, PostgreSQL, Maven, Liquibase, React, TypeScript, React Router, Vite, Node.js, Prisma, Zod, Docker, Docker Compose, GitLab CI/CD, Shopify CLI, Shopify App Bridge, Polaris, weclapp, i18next, Lombok, Vitest

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

• Automation of the database major / minor releases for the TKeasy project

• Concept for database major / minor release automation

• As-is analysis

• Evaluation of Redgate Flyway functionality

• Concept creation

• Products: Redgate Flyway, GitHub, Quest, Erwin Data Modeller, Oracle, Atlassian Jira, Atlassian Confluence

• Skills: Docker, Continuous Delivery, Continuous Integration, Redgate Flyway, Major Releases, Minor Releases

• Design, planning and execution of complex acceptance tests for a document exchange platform for the German justice authorities.
• Validation of decrypted and certificate-based message exchange via web platform, mobile app, and Java API.
• Documentation of test cases, execution steps, and test results.
• Technologies: Windows 11/10, Ubuntu, iOS, Android, Bash for Windows, Java 17, IntelliJ, Git, Jira, Confluence, Citrix Server, xJustiz standard implementation, specific justice software.

• Further development of a policy administration system (contract/claims) for the legal expenses insurer ÖRAG.
• My role: Senior Software Developer.
• The team consists of 12 developers.
• Technologies used: Java 8/21, Java EE, Quarkus, WebLogic, JPA, RabbitMQ, JTA, CI, CD, Jenkins, DB2, Maven, Jenkins, GIT (bitbucket) later GitLab, Junit, Elasticsearch, Mockito, Jira, SonarQube, Scrum, React, Workflow
• Migration and modernization of legacy systems: rewrote C and C++ code in Java to improve maintainability, scalability, and performance. Refactored Python into Java, including optimization and integration into modern architectures.
• Study on the use of AI (Codex) for implementing a Java feature. The goal is to compare the time spent and productivity of AI-supported development with a classic implementation by a developer. The results should show how strongly the use of AI affects development time and efficiency.
• Development of the following tariff calculators for the years 2024/2026: private, companies, doctors, farmers, owner-occupied G + H, landlords, traffic, club, top managers, sales representatives, special criminal law, savings bank, municipal, BayGT, doctors, Dehoga

• Full product responsibility from a business perspective: requirement analysis, UX design, product strategy, and go-to-market implemented without an internal dev team using fully AI-supported development (Claude Code / Anthropic)
• Technical differentiation: KRITIS-compliant air-gapped deployment (Windows/NSIS), GDT interface for PVS integration, DATEV-LODAS export for payroll
• Managed pilot operation with initial external client (Dormagen medical practice): structured requirement gathering, test support, error analysis, and release management
• Developed rollout and sales strategy for market entry in the segment of private practices and small medical centers
• Human-in-the-Loop development principle: business decision → AI implementation → manual review → approval → release – each sprint documented in Jira (TIME project), every change traceable via co-authored commits
• Product outcome: Tauri/Rust desktop app with GDT watcher, multi-tier model (Starter/Professional/Enterprise), cloud mirror on Hetzner/Traefik, complete ISMS framework based on ISO 27001 and BSI basic protection as product foundation
• Direct method validation for the test manager role: hands-on experience with quality assurance of AI-generated products from a user perspective, review gate discipline, release approval under GDPR and the EU AI Act

• Implementation of Infrastructure as Code (IaC) with Terraform to ensure a scalable, repeatable, and secure Azure infrastructure
• Implementation and optimization of CI/CD pipelines with Azure DevOps
• Management of container and server environments and AKS