Senior Software Developer (m/w/d) - Windows (Softwareentwickler/in)

We are seeking a Senior Software Developer to enhance our Windows application, a secure document editing and collaboration platform. In this role, you will be a hands-on technical developer responsible for designing and building scalable systems, making sound technical decisions, and collaborating effectively with team members.

What you'll do

Core Development

· Design and develop new features for the Windows client application using modern .NET technologies

· Build and maintain desktop applications that handle file management, application launching, and session lifecycle management

· Implement security features including argument validation, secure file handling, and authentication integration

· Optimize application performance and reliability in enterprise environments

Architecture & Design

· Design and implement scalable application architecture for Windows client deployments

· Apply service-oriented patterns and dependency injection for maintainability and extensibility

· Create reusable components and libraries for document handling and session management

· Evaluate and recommend technology solutions for new features

Integration & Deployment

· Develop installer packages and deployment automation for enterprise distribution

· Implement integration with server-side components and cloud services

· Build custom installation logic and system validation checks

· Ensure compatibility with enterprise Windows environments and Group Policy configurations

Quality Assurance & Testing

· Write comprehensive unit and integration tests to ensure code quality and reliability

· Develop automated testing strategies covering multiple scenarios

· Participate in code reviews and knowledge sharing with team members

· Participate in security reviews and threat modeling

Technical Collaboration

· Communicate technical decisions and architectural rationale to team members and stakeholders

· Partner with product and security teams to translate business requirements into technical solutions

· Share knowledge and best practices through documentation and technical discussions

What you'll bring

· 7+ years of professional software development experience

· 4+ years developing Windows desktop applications (.NET ecosystem preferred)

· Strong understanding of application lifecycle management and deployment strategies

· Experience with version control systems and collaborative development workflows

· Proven track record delivering production-grade enterprise software

· Proficiency in C# and modern .NET framework development

· Experience with Windows application development, UI frameworks, and Windows API integration

· Understanding of installer and packaging technologies

· Knowledge of security principles for desktop applications (encryption, secure storage, input validation)

· Experience with automated build and deployment systems

· Solid grasp of testing frameworks and testing methodologies

· Strong problem-solving and debugging abilities

· Clear communication and documentation skills

· Ability to take ownership of complex features and drive them to completion

· Self-motivated with strong attention to detail

· Experience working in Agile development environments

Essential Skills

· Technical depth combined with strong problem-solving abilities

· Ability to balance architectural vision with practical delivery timelines

· Collaborative approach to working with cross-functional teams

· Proactive approach to identifying and resolving technical risks

· Passion for building products that solve real business challenges

Nice to Have

· Knowledge of Windows Server deployment and management

· Background in security-focused software development

· Experience with PowerShell scripting and system automation

· Understanding of document management systems or content collaboration platforms

· Experience with enterprise authentication systems (Active Directory, SAML, OAuth)

· Knowledge of RDP (Remote Desktop Protocol) or Terminal Services

· Experience building cross-platform applications

· Familiarity with CI/CD pipeline development