Senior C# / .NET Software Engineer
Budapest
Full-time
Permanent employee
Your mission
Are you passionate about writing clean, high-quality code and building reliable software solutions? We are looking for a Senior C# Developer to join our growing development team in Budapest, working for a multinational leader in the telecommunications sector. In this role, you’ll contribute to cutting-edge projects that power secure and efficient communication systems across the Globe.
Your profile
Duties and responsibilities
- Design, implement and evolve scalable backend services using C# / .NET
- Contribute to microservices architecture and domain-driven design initiatives
- Own features end-to-end from technical design to production rollout
- Participate in architecture discussions and system evolution decisions
- Collaborate with cross-functional teams (Frontend, DevOps, QA, Product)
- Support modernization of legacy components into distributed systems
- Contribute to API design and internal platform capabilities
- Participate in improving CI/CD pipelines and DevOps maturity
- Contribute to observability, monitoring and reliability improvements
- Ensure high standards of code quality, maintainability and security
- Support integration with telephony, VoIP, financial and regulatory systems
- Take part in research and experimentation with AI-based solutions where applicable
- Mentor junior developers and contribute to knowledge sharing
Required Qualifications, Experience & Competencies
Professional Experience & Skills
- Core Engineering Foundation
- 5+ years of professional software engineering experience
- Strong foundation in computer science fundamentals (data structures, algorithms, distributed systems, system design)
- Ability to design scalable, maintainable and resilient systems
- Experience working on complex, mission-critical systems
- Deep understanding of backend architecture principles
- Strong API design and service-oriented architecture mindset
- Experience reasoning about performance, reliability and security
- Technology Adaptability
- Proficiency in at least one modern backend programming language (C#/.NET experience is highly valued, but strong engineers from other ecosystems are welcome)
- Experience working in distributed or microservices-based systems
- Solid database design knowledge (relational and/or NoSQL)
- Experience working with cloud environments (Azure preferred, but not mandatory)
- Comfort navigating hybrid (cloud + on-prem) environments
- Learning agility and architectural thinking over specific library knowledge
- AI & Modern Engineering Mindset
- Interest in applying AI-assisted development practices
- Openness to integrating AI-driven features into products
- Curiosity toward automation, intelligent workflows and experimentation
- Experience using modern AI development tools (Copilot, LLM-based workflows, etc.) is an advantage
- Growth mindset toward emerging technologies
- Active contribution to AI-enabled engineering workflows and intelligent product capabilities
- DevOps & Engineering Culture
- Understanding of CI/CD principles
- Ownership mentality and accountability for production systems
- Experience working in collaborative, cross-functional teams
- Desire to contribute to high-performance engineering culture
- English proficiency (written and spoken)
Advantages
- Experience in telecommunication systems (VoIP, SIP, RTP)
- Experience in highly regulated environments
- Experience with financial systems or billing engines
- Domain-driven design experience
- Experience contributing to DevOps transformation initiatives
- Exposure to AI-driven features or experimentation
Why us?
We are offering
- Professional challenges, inspiring, diverse tasks
- structured development process
- learning path on new technologies (AI, LLM)
- multiculture environment
- flexible working hours and home office days
- relaxed atmosphere, steady, supportive international team
- easily accessible modern office with good infrastructure
- complimentary coffee, fruit and snacks