C# Experts in Cologne
matched in minutes with vetted, available freelancersHire experts who build reliable .NET applications, APIs, desktop software and cloud services with C#, while connecting cleanly to databases, Azure and modern delivery pipelines. FRATCH finds the right vetted, available freelancer quickly and precisely.
Meet FRATCH Experts in Cologne, who have recently used C#
Burhan D.
Last position:
Enterprise Architect & Solution Architect at DB Netz AG
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
Yaroslav S.
Last position:
Senior Low-Code Consultant at Freelancer
Structured analysis and evaluation of business processes
Gathering, documenting, and prioritizing requirements
Creating business-friendly and technically executable process models
Use of Camunda tools
Deriving requirements and interfaces from BPMN diagrams
Coordination with stakeholders and business units
Translating business requirements into technical solution designs
Implementing efficient and tailored applications
Systematic collection, analysis, and documentation of requirements
Prioritizing and validating requirements in close collaboration with stakeholders
Alignment between business and development to ensure shared objectives
Creating use cases, user stories, and acceptance criteria
Continuous requirements and change management throughout the project lifecycle
Define project goals and create project plans
Delegate tasks and monitor project progress
Monitor budgets and inform stakeholders
Mendix: Architecture, development, and maintenance of custom applications (Microflows, Domain Model, Security, XPath)
Modeling Mendix workflows for process optimization
Develop scalable apps with Mendix including REST/SOAP integration with SAP, SQL, Azure & SharePoint
UI design for Mendix using Atlas UI, Fluent UI, HTML, CSS, JavaScript
Develop web & mobile apps with Mendix using agile methods (Scrum, Kanban)
Implement business logic with Mendix Microflows and Nanoflows
Performance optimization and architecture improvements for Mendix applications
Conduct Mendix training
Create technical documentation and best practices for Mendix
Coaching and mentoring for low-code development with Mendix
Andreas B.
Last position:
Senior Software Developer at ELIONOVA AG
- Created an application to control measurement hardware with a Tauri application using React.JS and TypeScript on Raspberry Pi
- Developed a cloud application for storing and analyzing measurement results using Spring Boot and React.JS
- Built a Tauri application for printing ZPL labels on Windows
- Technologies: Java, JavaScript, Tauri, Rust, React.JS, AWS, Kubernetes, Docker, GitLab CI/CD, REST API (JSON), Maven, CI/CD, PostgreSQL
Alexander K.
Last position:
Software Tester at Buhl Tax Service GmbH
- AI-assisted creation of test cases and test data
- Creation of test cases based on requirements
- Execution of manual tests
- Defect documentation, retesting and tracking
Technologies & Tools: SCRUM, Jira, Confluence, Zephyr Scale
Ahmed M.
Last position:
Senior Full-Stack Engineer at NEW NETZ
- Built more than 15 frontend applications and more than 10 backend services across internal tools, back-office workflows, and external portals for installers and end customers
- Automate build and release workflows with TypeScript and Azure DevOps
- Mentor junior engineers through code reviews and technical guidance
- Integrate AI-assisted and agentic development practices into engineering workflows
- Coordinate user experience decisions with UX designers
Tech Stack: Claude Code, Codex, AWS (S3, Lambda, AppSync, Resolver), Next.js App Router, ReactJS, NuxtJS, Vue.js, Storybook, JavaScript, TypeScript, GraphQL, Azure DevOps
Rainer L.
Last position:
Senior IT Consultant, Senior Software Architect, Senior Software Developer, Senior DevOps Engineer at Techniker Krankenkasse
Automation of the database major / minor releases for the TKeasy project
Concept for database major / minor release automation
Assessment of the current state
Evaluation of Redgate Flyway functionalities
Concept development
Products: Redgate Flyway, GitHub, Quest, Erwin Data Modeller, Oracle, Atlassian Jira, Atlassian Confluence
Knowledge: Docker, Continuous Delivery, Continuous Integration, Redgate Flyway, Major Releases, Minor Releases
Melanie T.
Last position:
Founder and Game Director at MELLOW Games UG (haftungsbeschränkt)
I won the "serious games funding" from the state of NRW in Germany at the end of 2023 for my game Blueberry. This gave me the chance to put together an international team of freelancers for programming, art, animation and audio. I developed the complete UI and UX as well as level and narrative design for the game, implementing the UI in Unity in close collaboration with my programmer. Blueberry will be released on Steam, Xbox, PS5 and Switch on 28th May 2026.
Andreas K.
Last position:
Backend Developer at Univention GmbH
- 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.
Stefan M.
Last position:
Bundesrechtsanwaltskammer
- 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.
Christoph S.
Last position:
Test Manager at Logistics
- 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
Nenad B.
Last position:
Safety Video Analytics Project for Airbus at Airbus
- Developed a real-time video analytics proof-of-concept for deployment on NVIDIA Jetson edge devices.
- Implemented DeepStream pipelines including object detection, tracking, human pose estimation, face anonymization, and zone intrusion detection.
- Built a Qt/Python demonstration UI interfacing with the AI pipeline via REST APIs.
Alexander R.
Last position:
Business Analyst at Financial Services Provider Landesbank
The Helaba ATLAS project aims to modernize core systems and make them future-proof. As part of the subproject, the existing legacy system for international payments is being replaced by a modern web-based application.
- Analysis of functional and technical requirements
- Analysis and optimization of business processes
- Process modeling
- Preparation and facilitation of workshops
- Defining project scope and prioritizing requirements
- Business process management (analysis, modeling, and optimization)
- Specification of user stories
- Designing business and authorization concepts
- Testing and acceptance
- Designing mockups in Figma
- Creating the UI/UX style guide for web applications Approach: Scrum (agile) Technologies: Jira, Confluence, MS Teams, Conceptboard, Java, Vaadin, Figma
Rodion O.
Last position:
Founder, CTO & Managing Director at MYNR Product Mining GmbH
- Responsible for the architecture and development of an AI-native SaaS platform for industrial product portfolio management.
- Designed the modern data platform architecture on Azure for scalable analytics and enterprise data integration.
- Built enterprise data ingestion and transformation pipelines across complex industrial system landscapes.
- Developed graph-based representations of product structures and dependencies for analytical reasoning.
- Designed and implemented an agentic AI framework for AI-supported decision workflows.
- Built scalable analytical microservices and integrated reporting through modern BI technologies.
- Coordinated backend, AI, and frontend development across the MYNR platform stack.
Ayhan G.
Last position:
Senior QA Engineer / Test Automation Engineer / SDET at Rewe digital
Consulting, designing, and implementing the software testing lifecycle for multiple Android apps and backends Introducing test automation with Appium, SpringBootTest, RestAssured Setting up and managing emulators Developing an E2E library, an integration library, a Testcontainers library, and other libraries Developing, implementing, and advising on CI strategies Building the test environment with Testcontainers and virtualization Developing and implementing test cases for integration tests and end-to-end tests Establishing a maintainable test architecture with low entry barriers to simplify the creation of automated tests Some tools and technologies used: JUnit, RestAssured, Testcontainers, Kubedock, Appium, Android emulator, Jira Xray, Mockito, WireMock, Spring Framework, Kotlin
Brahim A.
Last position:
Lead Developer at Blazor Web App at WAITS Software- und Prozessberatungsgesellschaft mbH
- Web development with Blazor
- Two-factor authentication for Blazor applications
- Uploading and downloading files
- Bug fixes for existing applications
- Programming interfaces
- Integration of third-party tools and technologies
- Creation of developer tests (unit tests)
Discover over 15,000 top freelancers
Statistics of experts using C#
Aggregated from the professional profiles of matched freelancers.
Experience
21 years (Germany: 20 years)
Position duration
2.9 years
Positions per freelancer
14
Top business areas
Information Technology, Product Development, Quality Assurance
Top industries
Information Technology, Government and Administration, Banking and Finance
Certification focus areas
Project Management, Information Technology, Product Development
Bachelor's degree or higher
95% (Germany: 88%)
Master's degree or higher
77% (Germany: 53%)
Doctorate
5% (Germany: 8%)
Certifications per freelancer
3
Most common languages
German, English, French
Speak two or more languages
100% (Germany: 97%)
Based on our profile pool as of 29 Oct 2026.
Daily rate distribution
The chart shows how the daily rates of experts in this technology in Cologne are distributed, based on recent contracts on our platform. Each bar covers a rate range — its height shows the share of experts charging within that range.
Average rates of experts in Cologne using C#
Rates are based on recent contracts and do not include FRATCH margin.
The average daily rate is the mean of all daily rates from recent contracts of comparable freelancers on our platform.
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.
Calculated based on our freelancers’ daily rates as of 29 Oct 2026. Actual rates may vary depending on seniority level, experience, skill specialization, project complexity, and engagement length.
C# experts industry focus
See which industries our matched freelancers work in most often — every figure is calculated live from the freelancers on FRATCH.
- Information Technology (100%)
- Government and Administration (52%)
- Banking and Finance (44%)
- Transportation (44%)
- Manufacturing (44%)
- Automotive (37%)
- Healthcare (30%)
- Professional Services (30%)
Please note that freelancers can work across multiple industries, so percentages overlap.
About the technology
C# at a glance
C# is a strongly typed language from Microsoft for building software across the .NET ecosystem. It supports object-oriented, functional and asynchronous programming, making it suitable for business systems, web services, desktop applications, games and cloud workloads. Its tooling combines language safety with fast development.
What C# builds
C# specialists deliver software that needs dependable business rules, maintainable code and integration with existing systems.
- ASP.NET Core websites, REST APIs and backend services
- Windows desktop applications with WPF or Windows Forms
- Unity games and interactive real-time experiences
- Azure functions, event-driven services and data workflows
- Internal tools connected to ERP, CRM and database systems
The .NET ecosystem
C# work commonly includes .NET, ASP.NET Core, Entity Framework Core, LINQ and dependency injection. Strong professionals also understand SQL databases, REST, JSON, authentication, automated testing and container-based delivery. Azure services, Git workflows and CI/CD pipelines often complete the project environment.
When companies bring in experts
Freelance C# expertise helps when an application needs a new service, a legacy system needs a safe extension or an internal team needs capacity for a defined delivery phase. Cologne companies can work with specialists remotely or on site, depending on security, workshops and stakeholder needs. German or English collaboration can be agreed before the project starts.
- A monolithic .NET application needs modularisation
- APIs must connect products, partners or business systems
- Performance, reliability or test coverage is holding back delivery
- A team needs support with Azure deployment and observability
What strong specialists bring
Good C# professionals choose clear abstractions instead of unnecessary complexity. They know when to use asynchronous code, how to model domain rules and how to protect APIs with robust authentication and validation. They also explain trade-offs, document decisions and leave code that the internal team can operate.
Choosing the right fit
Review shipped work that resembles the system being built, not just a list of frameworks. Ask how the specialist handles testing, database changes, error handling, monitoring and technical debt. A useful technical discussion should cover the current architecture, expected deliverables, collaboration style and how knowledge will transfer to the team.
Frequently asked questions
Need clarity? These are the questions we hear most often about C#.
C# is used for web applications, APIs, desktop software, cloud services, business systems and games made with Unity. It is especially useful when a project needs strong integration with .NET, Microsoft services, relational databases or enterprise identity systems.
C# and Java both support strongly typed, object-oriented application development and large enterprise ecosystems. C# is closely integrated with .NET and Azure, while TypeScript is primarily used around JavaScript runtimes and browser applications; the best choice depends on the existing stack, deployment model and team skills.
A strong C# freelancer often works with ASP.NET Core, Entity Framework Core, SQL, REST APIs and automated testing. Experience with Azure, Docker, CI/CD, message brokers, authentication and observability is valuable when the work extends beyond application code.
The right level depends on the system’s risk, scope and existing documentation. A contained API feature may need focused framework knowledge, while a migration, high-availability service or legacy .NET system benefits from a specialist who has handled architecture, production incidents and incremental delivery.
Yes. C# projects suit remote collaboration when repositories, environments, acceptance criteria and review routines are well organised. For Cologne teams, remote work can be combined with on-site workshops when domain discovery, security reviews or close stakeholder collaboration require it.
C# is a strong choice when a company already relies on .NET, Microsoft identity, Azure or Windows-based systems. It also fits teams that value compile-time checks, mature tooling and a broad framework ecosystem; another technology may be preferable when a project has very different runtime or community requirements.
Ask a C# specialist to explain a comparable system, including its boundaries, tests, data access and operational risks. Look for clear reasoning about async code, error handling, security, performance and maintainability rather than familiarity with framework names alone.
Yes. C# specialists are often brought in to maintain or modernise older .NET applications while protecting business-critical behaviour. Useful experience includes dependency assessment, incremental migration, regression testing, integration replacement and clear planning for changes that cannot be made all at once.
The average hourly rate of freelancers in Cologne, Germany who have used C# in their recent projects is 90 €, which corresponds to a daily rate of about 719 € based on an 8-hour working day.
Of the freelancers in Cologne, Germany who have used C# in their recent projects, 95% hold at least a Bachelor's degree, 77% hold at least a Master's degree, and 5% hold a doctorate.
On average, freelancers in Cologne, Germany who have used C# in their recent projects have 21 years of professional experience, with a single engagement typically lasting around 2.9 years.
The most common languages among freelancers in Cologne, Germany who have used C# in their recent projects are German (100%), English (100%), and French (15%).
The most common industries among freelancers in Cologne, Germany who have used C# in their recent projects are Information Technology (100%), Government and Administration (52%), and Banking and Finance (44%).
The most common business areas among freelancers in Cologne, Germany who have used C# in their recent projects are Information Technology (100%), Product Development (100%), and Quality Assurance (67%).
Main locations of FRATCH Experts, who have recently used C#
Our freelancers and interim experts are at home across the DACH region — available on-site in the major business hubs or fully remote. Choose a location to discover matched specialists, local market insights and up-to-date availability.
Berlin 
Hamburg 
Munich 
Frankfurt 
Stuttgart 
Dusseldorf 
Dortmund 
Essen 
Bremen 
Nuremberg Request a free demo
Get in touch with the FRATCH team and we will get back to you within 4 hours.
Would you rather directly get in touch?
We always have the time for a call or email!
Philipp Thomaschewski
FRATCH CEO
