Stefan Kassler - C# .NET/WPF Developer

Q: Where is Stefan based?

Stefan is based in Halle (Saale), Germany and can operate in on-site , hybrid , and remote work models.

Q: What languages does Stefan speak?

Stefan speaks the following languages: German (Advanced), English (Advanced) .

Q: How many years of experience does Stefan have?

Stefan has at least 13 years of experience. During this time, Stefan has worked in at least 11 different roles and for 11 different companies . The average length of individual experience is 1 year and 2 months . Note that Stefan may not have shared all experience and actually has more experience.

Q: What is Stefan's latest experience?

Stefan's most recent position is C# .NET/WPF Developer at Hessian Central Office for Data Processing .

Q: What companies has Stefan worked for in recent years?

In recent years, Stefan has worked for Hessian Central Office for Data Processing , Brooks Automation (Germany) GmbH , and TQ-Systems GmbH .

Q: Which industries is Stefan most experienced in?

Stefan is most experienced in industries like Information Technology , Manufacturing , and Energy . Stefan also has some experience in Automotive , Healthcare , and Education .

Q: Which business areas is Stefan most experienced in?

Stefan is most experienced in business areas like Information Technology , Product Development , and Project Management . Stefan also has some experience in Research and Development and Quality Assurance .

Q: Which industries has Stefan worked in recently?

Stefan has recently worked in industries like Manufacturing , Education , and Government and Administration .

Q: Which business areas has Stefan worked in recently?

Stefan has recently worked in business areas like Information Technology , Project Management , and Product Development .

Recommended expert

Halle (Saale), Germany

Check rate

Experience

Nov 2023 - Jul 2024

9 months

C# .NET/WPF Developer

Hessian Central Office for Data Processing

New development of outdated software for the Hessian school system in C# .NET/WPF
Understanding and analysis of the old Delphi and Visual Basic 6 source code
Use of Visual Studio 2022 as IDE
Team collaboration through pull requests and version control with Git/SourceTree
Project management with our own wiki software and Open Project
Tech stack: C#, .NET 8.0, WPF, Visual Studio 22, Delphi, Visual Basic 6, LDAP, Active Directory, FTP, SMB, Git, SourceTree
Workflow: pull requests, Open Project, weeklies, weekly meetings, direct communication

May 2023 - Jun 2023

2 months

C#/.NET Developer

Brooks Automation (Germany) GmbH

Further development of the operating software for complex semiconductor cleaning machines according to SEMI standard
Background communication with PLC software for machine control
Use of Spring.NET Framework alongside standard .NET components
Development in Visual Studio 2019 with ReSharper
Team collaboration via pull requests and version control with Git/SourceTree
Project management with Atlassian Confluence and Azure DevOps
Introduction of a SCRUM model with daily stand-ups
Communication completely in English
Tech stack: C#, .NET Framework, Spring.NET, Git, SEMI Standard, Visual Studio 2019, ReSharper, PLC, Semiconductor

Jan 2022 - Sep 2022

9 months

Full-Stack Developer

TQ-Systems GmbH

Further development of apps on embedded devices with Go in the backend and Vue.JS in the frontend
Development in Ubuntu 20.04 LTS VM with Visual Studio Code
Containerization of each app in Docker containers
Quality assurance through unit tests in Go and integration tests with Cypress
Team collaboration with merge requests and version control via GitLab
Automated pipelines in GitLab CI for tests on merge requests
Project management with Jira and Confluence in the SCRUM framework (dailies, weeklies, sprint meetings, retros)
Tech stack: Go, Vue.JS, JavaScript, GitLab, Docker, Ubuntu, Visual Studio Code, Webpack, Cypress, MQTT, Modbus, D-Bus, Yocto, Yarn, BASH, microservices, REST API

Jan 2020 - May 2021

1 year 5 months

Freelance C#/.NET Developer

E.ON Digital Technology GmbH

Ongoing operation and maintenance of an old CRM application in C#/.NET
Provision of call scripts in form layout via vue.js and RTI Designer
Development in Visual Studio 2019, RTI Designer and Visual Studio Code for vue.js/JavaScript
Version control with TortoiseGit
Project management with Jira and Confluence in the SCRUM model (dailies, weeklies)
Tech stack: C#, .NET, JavaScript, Vue.JS, node.js, CSS, HTML, RTI Designer, REST API, web services, microservices, SoapUI, Postman, Git Bash, TortoiseGit, CosmosDB, AWS

Jan 2019 - Mar 2019

3 months

Freelance Software Developer

DAVASO GmbH

Analysis and full documentation of a codebase that had grown over 13 years within 2 months
Adaptation of the software to new legal requirements
Work with Transact-SQL on MS SQL Server, C++ and C#/.NET components as well as Perl programs
Adaptation and further development of the customer homepage with PHP 7/Zend 1/Composer/Smarty and prototypeJS
Development tools: various Visual Studio versions, MS SQL Server Management Studio, Eclipse Oxygen 3
Version control with WinCVS
Project management with Jira and wiki in the SCRUM framework (dailies, sprints)
Tech stack: C#, .NET, C++, MS-SQL Server 2008, PHP 7, Zend 1, JavaScript, jQuery, prototypeJS, Transact-SQL, Composer, Smarty, Perl

Jul 2018 - Dec 2018

6 months

Unity3D/VR Developer

Carmeq GmbH

Further development of a comprehensive driving simulation with VR integration
Simulation of driving and loading scenarios for electric cars with hardware feedback (steering wheel, pedals)
Use of HTC Vive Pro and Leap Motion for hand tracking
Development in Unity3D with VRTK and Visual Studio
Project management with Jira and Confluence
TechStack: Unity3D, C#, mono, VR, AR, HTC Vive Pro, Leap Motion, SVN

Aug 2017 - Sep 2018

1 year 2 months

Delphi Developer

form & function GmbH

Development of a database application in Delphi for planning maintenance processes based on sensor input from industrial plants
Calculation of wear and maintenance intervals
Connection to PostgreSQL database and existing software portfolio
TechStack: Delphi 10.2, PostgreSQL, zeoslib, dcpcrypt2

Nov 2016 - Aug 2017

10 months

VR Learning Software Developer

LeFx GmbH

Implementation of a VR learning software with gamification elements for the automotive industry
Development of a scenario editor and a custom scripting language with parser and interpreter
Use of Unity3D with VRTK and HTC Vive hardware
Project management with Jira and Confluence
TechStack: Unity3D, C#, mono, VRTK, HTC Vive, UniRx, Perforce

Apr 2015 - May 2016

1 year 2 months

Lead Gameplay Developer

FAKT Software GmbH

Development of level and object editors for "Crazy Machines 3" on the company's own engine
Implementation of complex mathematical functions
Development in C++ with Visual Studio and in-house engine
Version control with Git (SourceTree GUI)
Project management with Jira and Confluence in the SCRUM model (dailies, one-week sprints)
TechStack: C++, 3D programming, physics programming, Visual Studio 13/15

Oct 2013 - Sep 2014

1 year

Startup Software Developer

EXIST scholarship

Independent work on a medical software for the early detection of vascular diseases through OCT image analysis
TechStack: Delphi 7, image processing, medical software

Mar 2008 - Sep 2013

5 years 7 months

Founder and Developer

SAFKAS Games

Founded and ran my own software company during my studies
Developed games in Delphi 7 and Andorra2D
Built small web projects and my own homepage in PHP and JavaScript
Tech stack: Delphi 7, Andorra2D, PHP, JavaScript, MySQL, HTML, CSS

Industry Experience

See where this freelancer has spent most of their professional time.

Experienced in Information Technology, Manufacturing, Energy, Automotive, Healthcare, and Education.

Information Technology

Manufacturing

Energy

Automotive

Healthcare

Education

Business Area Experience

See which departments and functions this freelancer has contributed to most.

Experienced in Information Technology, Product Development, Project Management, Research and Development, and Quality Assurance.

Information Technology

Product Development

Project Management

Research and Development

Quality Assurance

Skills

Programming: C#, .Net, Wpf, C, C++, Vue.Js, Javascript, Delphi, Php, Unity3d, Go, Mysql, Ms Sql, Postgresql, Css, Html, Perl, Bash, Typescript, Basic, Turbo Pascal
General Working Style: Agile Software Development, Scrum, Object-Oriented Programming, Leading My Own Development Teams, Documenting Source Code And Projects, An Eye For Software Architecture, Creating Requirements Specifications, Strong Communicator, Team Player, Performance-Oriented
Ides: Visual Studio, Visual Studio Code, Rti Designer, Delphi (2, 5, 7, Xe2, 10, 11), Unity3d, Eclipse
Toolchain: Git, Gitlab, Svn, Sourcetree, Perforce, (Win)Cvs, Docker, Ansible, Cypress, Soapui, Postman, Yocto
Frameworks / Components - Web Development: Vue.Js, Node.Js, Webpack, Angular, Jquery, Symfony, Zend, Prototypejs, Composer, Enyo
Frameworks / Components - C#: .Net, Wpf, Spring.Net, Unity3d, Vrtk, Unirx
Frameworks / Components - Go Lang / Embedded Systems: Modbus, D-Bus, Plc
Frameworks / Components - Delphi: Zeoslib, Unidac, Mydac, Dcpcrypt2, Andorra2d
Frameworks / Components - General: Mqtt, Microservices, Rest Api, Web Services
Collaboration: Jira, Confluence, Azure Devops, Mantis Bt, Trello, Ms Teams, Skype, Rocket.Chat, Zoom, Discord, Bbb
Hardware: Htc Vive Pro, Leap Motion, Microsoft Hololens
Formats: Json, Xml, Html, Css, Rauc, Pdf, Word, Excel
Operating Systems: Windows (Since 95), Ubuntu (Since 18.04), Ms-Dos (Since 3.0)

Languages

German

Advanced

English

Advanced

Education

Oct 2001 - Jun 2010

University of Leipzig

Magister · Computer Science, Logic and Philosophy of Science · Leipzig, Germany

Statistics

Experience

Total positions 11

Experience in Information Technology 7.5 y

Avg length 1 y 2 m

Longest experience 5 y 6 m

Expertise

Recent roles C# .NET/WPF Developer, C#/.NET Developer, Full-Stack Developer

Main industries Information Technology, Manufacturing, Energy

Main business areas Information Technology, Product Development, Project Management

Qualifications

Highest degree Master

Profile

Created

June 2025

Last Update

July 2026

Need a freelancer? Find your match in seconds.

Try FRATCH GPT

Frequently asked questions

Have questions? Find more information here.

Stefan is based in Halle (Saale), Germany and can operate in on-site, hybrid, and remote work models.

Stefan speaks the following languages: German (Advanced), English (Advanced).

Stefan has at least 13 years of experience. During this time, Stefan has worked in at least 11 different roles and for 11 different companies. The average length of individual experience is 1 year and 2 months. Note that Stefan may not have shared all experience and actually has more experience.

Based on recent experience, Stefan would be well-suited for roles such as: C# .NET/WPF Developer, C#/.NET Developer, Full-Stack Developer.

Stefan's most recent position is C# .NET/WPF Developer at Hessian Central Office for Data Processing.

In recent years, Stefan has worked for Hessian Central Office for Data Processing, Brooks Automation (Germany) GmbH, and TQ-Systems GmbH.

Stefan is most experienced in industries like Information Technology, Manufacturing, and Energy. Stefan also has some experience in Automotive, Healthcare, and Education.

Stefan is most experienced in business areas like Information Technology, Product Development, and Project Management. Stefan also has some experience in Research and Development and Quality Assurance.

Stefan has recently worked in industries like Manufacturing, Education, and Government and Administration.

Stefan has recently worked in business areas like Information Technology, Project Management, and Product Development.

Stefan holds a Master in Computer Science, Logic and Philosophy of Science from University of Leipzig.

Stefan is immediately available full-time for suitable projects.

Stefan's rate depends on the specific project requirements. Please use the Meet button on the profile to schedule a meeting and discuss the details.

To hire Stefan, click the Meet button on the profile to request a meeting and discuss your project needs.

Salary / Daily Rate Distribution

0 1 2 3 4

<€640 €640-720 €720-800 €800-880 €960-1040 €1040+

The rates shown represent the typical market range for freelancers in this position based on recent contracts on our platform.

Actual rates may vary depending on seniority level, experience, skill specialization, project complexity, and engagement length.

Average rates for similar positions

Rates are based on recent contracts and do not include FRATCH margin.

800

600

400

200

Daily rate avg. 795 €

The average daily rate is the mean of all daily rates from recent contracts of comparable freelancers on our platform.

800

600

400

200

Median rate 760 €

The median daily rate is the middle value of all daily rates — half of comparable freelancers charge less, half charge more. Unlike the average, it is barely affected by outliers.

Actual rates may vary depending on seniority level, experience, skill specialization, project complexity, and engagement length.