Full Stack Engineer
Full Stack .NET Engineer (Voice / Telephony Platform)
We are looking for a .NET Engineer to join a product development team working on a voice communication and conversation analytics platform.
The product supports real-time voice communications, call recording and processing, and integrations with telephony providers, contact center solutions, and CRM platforms.
The role is primarily focused on backend development with C#/.NET. We are looking for an engineer with solid backend expertise who is comfortable working with APIs, integrations, databases, and real-time systems.
Experience in telephony, VoIP, WebRTC, SIP, UCaaS/CCaaS, or contact center solutions would be a strong advantage.
Tech Stack
C# / .NET 6+ · ASP.NET Core · MS SQL · REST APIs · SignalR · WebSockets · Twilio · WebRTC · Azure · React.js / TypeScript
Responsibilities
- Develop and maintain backend services using C# / .NET
- Build new functionality for voice communication and call recording
- Work with end-to-end call flows, including call initiation, routing, recording, storage, and retrieval
- Design, develop, and maintain REST APIs
- Build integrations with telephony providers, communication platforms, contact center systems, and CRMs
- Develop real-time functionality using SignalR, WebSockets, WebRTC, and Twilio
- Work with relational databases and optimize data access
- Troubleshoot issues related to call flows, third-party integrations, and real-time communications
- Improve application performance, reliability, and scalability
- Participate in technical discussions, estimations, and code reviews
Collaborate with Product, QA, and Engineering teams throughout the development lifecycle
Requirements
- 3+ years of commercial software development experience
- Strong commercial experience with C# / .NET
- Good knowledge of ASP.NET Core
- Solid understanding of backend development and client-server architecture
- Experience developing and integrating REST APIs
- Experience with relational databases and SQL
- Good understanding of asynchronous programming and concurrency
- Experience working with integration-heavy and/or real-time systems
- Understanding of software architecture principles, design patterns, and clean code practices
- Experience with Git and modern development workflows
English — B2+
Key Experience
- Experience with telephony, VoIP, UCaaS/CCaaS, contact center, or voice communication products
- Knowledge of SIP and RTP
- Experience with WebRTC
- Experience with call recording, audio/media processing, or real-time media streaming
- Experience with Twilio or similar communication APIs
- Experience with SignalR / WebSockets
- Integration experience with RingCentral, Microsoft Teams, Zoom, Cisco Webex, Avaya, 8x8, Genesys, Five9, or similar platforms
- Experience troubleshooting network, connectivity, or voice communication issues
- Experience with Azure
- Experience with microservices or distributed systems
- Docker and CI/CD experience
- React.js / TypeScript knowledge
- Experience with transcription, speech-to-text, conversation analytics, or AI/NLP solutions
What’s In It for You?
- Career Growth – Opportunities to develop and advance.
- Performance Reviews – Regular feedback and support.
- Work Anniversaries – Special gifts to celebrate milestones.
- Flexible Work – Hybrid or remote (Lviv office available).
- Mentorship – Guidance from experienced professionals.
- Accounting Support – We handle the paperwork.
- Paid Time Off – 18 vacation days + 5 sick days per year.
- Extra Leave – 10 additional days off annually.
- Free Office Lunches – Enjoy meals on us.
- Team Events – Gatherings, gifts, and a welcoming atmosphere.