Joachim Kuhn, Developer in Neu-Isenburg, Hessen, Germany
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Joachim Kuhn

Verified Expert  in Engineering

Software Developer

Neu-Isenburg, Hessen, Germany
Toptal Member Since
May 27, 2021

Joachim is a passionate C# programmer who likes working with SQL Server databases for data analysis, creating libraries (DLLs) or WinForms applications for solving complex problems, and using SQL directly or Entity Framework for data operations. Joachim has more than 20 years of experience.



Preferred Environment

Windows, Visual Studio, C#.NET WinForms, C#.NET

The most amazing...

...thing I've developed is accounting and order processing software.

Work Experience

Senior Developer

2018 - PRESENT
  • Developed and extended a large number of C# libraries and WinForms programs to calculate asset ratings and maintain asset data for a rating agency.
  • Used Jira Kanban boards for project tracking, Confluence for documentation, and TFS and Git as a versioning system.
  • Created a new rating algorithm for awards ranking. Migrated quote retrieval to Azure Functions.
Technologies: C#, Kanban, C#.NET WinForms

Senior Developer

2010 - 2018
  • Migrated accounting and order processing software from C++ and MFC to C#, implementing continuous development and improvement.
  • Added functionality to comply with GDPR. Implemented E-Bilanz (Taxonomy 6.0 and 6.1) for online submission of balance sheet.
  • Evaluated the complex structure of XBRL and created routines to read and process the elements.
Technologies: C#.NET WinForms

Senior Consultant

2017 - 2017
  • Created a basic and detailed concept for the implementation of SharePoint as an audit-proof document repository for a German bank.
  • Created Excel files for migrating legacy data to SharePoint via REST API.
  • Created PowerShell scripts for fast provisioning of new website collections.
  • Trained all personnel in handling SharePoint lists and libraries.
Technologies: SharePoint

Senior Developer

2016 - 2016
  • Implemented a CapEx portal with SharePoint 2010 and InfoPath 2010 using Nintex Workflow for the approval process.
  • Analyzed the paper-based process and designed an online process.
  • Created and filled SharePoint lists to configure the approval process with Nintex Workflow.
Technologies: SharePoint, InfoPath, Nintex Workflow

Senior Developer

2015 - 2015
  • Created a C# application for metadata management of decor and image data.
  • Provided lists in SharePoint and filled by C# app for metadata search.
  • Implemented queue processing with RabbitMQ for worldwide image data transfer.
Technologies: C#, RabbitMQ

Application Developer

1996 - 2015
  • Created and extended accounting and order processing software with C++ and MFC.
  • Implemented an EDI interface for submission of orders to distributors and receiving delivery status updates and invoices.
  • Applied additions according to customer requirements for webshop data and reportings.
Technologies: C++, Microsoft Foundation Class (MFC) Library, Microsoft Foundation Classes (MFC)

Senior Developer

2012 - 2012
  • Created a risk appraisal solution in SharePoint 2010 with InfoPath 2010.
  • Analyzed workflows for implementation as an online solution.
  • Created custom workflow activities with C# and used them in SharePoint 2010 workflow for the risk appraisal approval.
Technologies: SharePoint, InfoPath

Senior Developer

2010 - 2010
  • Built a webshop based on osCommerce, creating import routines in C# to transfer orders into order processing software.
  • Created an export routine to transfer shipping data to DHL software (Easylog).
  • Optimized the shipping process with scanner and barcode processing for delivery status.
Technologies: C#, osCommerce

Accounting and Order Processing Software

Developed C# programs to maintain the accounting system, post to the accounts, maintain articles, create offers, order confirmations, delivery notes, and invoices, and create all statutory reports. Used ERIC API to submit advance VAT return and balance sheet.

CapEx Portal

A SharePoint-based portal for the acquisition of investment applications. I created several lists to control the workflows and avoid modifying the workflow when approving managers changed. The form to enter the data was implemented with InfoPath and the workflow with Nintex.

WinForms App and Libraries for Asset Management and Rating Calculation

A C#-based application for maintaining asset data, such as issuer or prices, and libraries for calculating the monthly rating. A large amount of data from providers is imported every month through SSIS packages. I added the import of new important indicators (ESG and SRI), optimized the database, and created a new tool for ad-hoc data analysis.

Portal as Audit-proof Document Store

A SharePoint-based portal to store documents of a German bank. I created all necessary concepts, websites, libraries, and templates for every department and documentation area. I created the system documentation and trained all employees to use the portal. For migration of existing data, I created VBA macros in Excel to use the REST API of SharePoint.

Approval Portals

SharePoint-based approval portals for vacation, travel, and CapEx. Analyzed the paper-based forms and approval processes, and then I created InfoPath forms and control lists for approval with Nintex Workflow.

App for Image Metadata

A C# program to enter and update metadata (classification) of decor and image files. This data was uploaded to SharePoint for metadata search. Another C# program used RabbitMQ to transfer decor and images to other offices worldwide for surface production.

Migration of a DOS-based Environment to WinForms

I replaced the complete DOS-based application environment for order processing with my accounting and order processing software, implemented the data transfer from osCommerce into the order processing system, created a module to transfer the shipping data to DHL Easylog, and made tracking data available for the shipped orders.
1984 - 1987

State-certified Computer Scientist in Business Informatics

Akademie für Datenverarbeitung - Böblingen, Germany

AUGUST 2021 - AUGUST 2022

Microsoft Certified: Azure Developer Associate



Microsoft Certified: Azure Fundamentals



Machine Learning

Stanford University | via Coursera


MCSA Windows Server 2012/R2



MCITP Windows Server 2008



MCITP SQL Server 2005



MCDBA SQL Server 2000



Windows Forms (WinForms), LINQ, Entity Framework


C#.NET WinForms, Visual Studio, Hyper-V, ISPF, JCL, RabbitMQ


.NET, .NET Core


C#.NET, C#, T-SQL (Transact-SQL), SQL, COBOL, PL/1, Excel VBA


Microsoft SQL Server, SQL Server Integration Services (SSIS), MVS, Azure SQL, Azure Storage, Azure Websites


ETL, DevOps, Kanban, Anomaly Detection, Microservices


Windows, Windows Server, Windows Server 2008, Windows Server 2012, osCommerce, Azure, Azure IaaS, Azure Functions, Azure Event Hubs

Industry Expertise



Finance, S/370 Assembler, TSO, VM, Programming, Organization, XBRL, Neural Networks, Deep Learning, Classification, Azure Service Bus

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