Freelancer profile translated to English.

Description

Freelance developer focusing on C#, .NET, WPF, and SQL. Experience in implementing Windows desktop applications, automation processes, and database-centric development. I have worked for consultancies, medium-sized companies, and corporations – including in the areas of data processing, Excel automation, ETL procedures, and UI enhancement.

Core Competencies & Focus Areas:

Development and extension of WPF/WinForms desktop applications
Building and maintaining SQL structures, T-SQL procedures, and database-centric logic

Automation of Excel/data processes (VBA, C#, Office interoperability)
Creation of custom tools for data processing, mapping, reporting, and conversion
API integrations, data-driven workflows, and import/export logic
Performance optimization, error analysis, and stability improvements
Development of modular desktop systems including scheduling, price list logic, and management tools

Technologies:

C#, .NET, WPF, SQL/T-SQL, SSIS, VBA, JSON/XML processing, Office automation, Git

Industry field of expertise

Languages

German
Native or bilingual
English
Conversational

Workplace preferences

Remote only

Primarily works remotely

Ernst & Young Real Estate GmbH
T-SQL & ETL Developer
June 2023 - December 2024 (1 year and 6 months)
Support in the development and maintenance of SQL-based ETL processes in the data warehouse environment.
Collaboration on T-SQL procedures, optimization of existing ETL pipelines, and technical support
for SSIS loading chains as part of DWH expansion.

Typical tasks:
• Analysis, adaptation, and extension of T-SQL Stored Procedures
• Optimization of data flows in existing ETL pipelines
• Participation in automations and data validations
• Collaboration with the internal DWH team in ongoing project operations
Transact-SQL SQL ETL SSIS
Conficio Consulting GmbH
VBA / Excel Automation Developer
November 2024 - December 2024 (1 month)
Development of an Excel-based automation for creating HR job profiles
for Tom Tailor. Implementation of logic adjustments, data validation, and Word export via VBA
as well as corrections to existing templates.

Typical tasks:
• Extension and adaptation of existing VBA macros
• Automated transfer of Excel job data into Word templates
• Data mapping, validation, and handling of different Office versions
Macro VBA Excel Data processing XML JSON Debugging
Saliq GmbH
Software Developer (C#, .NET, WPF, SQL)
SOFTWARE PUBLISHING
July 2024 - Today (1 year and 11 months)
Zülpich, Germany
Full-stack development of a proprietary practice management system for therapy practices. Sole responsibility for the entire
software architecture, including the desktop client (C#, .NET, WPF) and relational SQL database.

Typical tasks and responsibilities:
• Development of a modern WPF desktop application for appointment scheduling, patient management,
employee management, and billing
• Conception and implementation of the complete SQL data model (tables, procedures, TVPs)
• Building a modular system with calendar view, price list module, prescription management,
and automated data checks
• Development of interactive UI components (e.g., calendar, taskbar, data grids)
• Implementation of complex business logic (appointment rules, validations, billing specifications)
• Optimization of performance, data flows, and UI interactions
• Planning for future product maturity and commercial use
.NET WPF SQL Transact-SQL UI/UX Design