Role Overview – RocketPhone.ai, a seed-stage startup building an AI-powered telephony solution that integrates with Salesforce, is hiring a Senior .NET Back-end Developer with 5+ years of professional experience for a full-time remote position (UK/Europe). This high-impact role as one of our first key engineering hires offers the opportunity to directly shape our core product, eliminate manual data entry for sales teams, and provide real-time conversational intelligence that helps close deals faster.

Back-End Architecture and Ownership – You will take full ownership of our core microservices, driving architectural decisions as a strategic partner rather than just a coder. Your responsibilities include designing the technical architecture, making critical technology decisions, establishing coding standards and best practices, and ensuring the scalability, reliability, and performance of our back-end infrastructure.

API and Service Development – You will architect, design, develop, and deploy highly scalable APIs and services using C# and the latest .NET framework. This includes building RESTful APIs, implementing business logic, optimizing performance, ensuring security best practices, and creating robust, maintainable code that supports our AI-powered telephony solution.

DevOps Excellence – You will champion code quality and testing while contributing to the CI/CD pipeline using Docker, Kubernetes, and modern DevOps tools. Your responsibilities include implementing automated testing, establishing deployment pipelines, monitoring system health, optimizing infrastructure, and promoting DevOps culture within the engineering team.

.NET Expertise – 5+ years of professional experience with C# and .NET (Core/6+/Entity Framework) is mandatory. You must demonstrate deep knowledge of the .NET ecosystem, proficiency in building enterprise-level applications, understanding of design patterns, and experience with the latest .NET framework features and capabilities.

Data and API Proficiency – Expertise in building APIs and services along with proficiency in SQL databases (PostgreSQL/SQL Server) is required. You should be skilled at database design, query optimization, data modeling, implementing efficient data access layers, and ensuring data integrity across distributed systems.

Cloud and DevOps Experience – Hands-on experience with a major cloud platform (GCP, AWS, or Azure) and modern DevOps tools is essential. You must be comfortable with cloud-native architecture, containerization with Docker, orchestration with Kubernetes, infrastructure as code, and implementing continuous integration and deployment pipelines.

How to Apply:

Interested candidates should send their resume to max@rocketphone.ai with the subject line "Senior .NET Back-end Developer Application - [Your Name]". Please highlight your 5+ years of professional experience with C# and .NET, including specific projects where you've built scalable APIs and microservices.

About Company:

RocketPhone.ai is a seed-stage startup revolutionizing sales productivity through AI-powered telephony solutions integrated with Salesforce. Our platform eliminates manual data entry and provides real-time conversational intelligence, enabling sales teams to close deals faster and work more efficiently. Founded by ex-Google engineers, AI researchers, and industry veterans, we're building the future of intelligent business communications.