Sr Software Engineer

About Our Client

Sinch operates in the communications technology industry, providing a Customer Communications Cloud platform that supports mobile messaging, voice, and email interactions. The organization addresses the challenge of enabling reliable and secure customer engagement across multiple channels for over 150,000 businesses globally, including major clients such as Google, Uber, and Visa. Sinch integrates AI capabilities to enhance communications and improve customer experience.

About the Opportunity

The Senior Software Engineer role focuses on designing, building, and scaling a conversational AI platform that supports real-time, distributed text and voice interactions. This position contributes to evolving the platform toward an intelligent orchestration system that combines AI agents and deterministic workflows, enhancing customer problem-solving capabilities. The engineer will drive technical decisions, foster system health, and help the team ship solutions efficiently in a dynamic environment.

Responsibilities

• Design and develop backend services for text and voice channels, including WebSocket servers and real-time communication infrastructure
• Work on platform integrations and application integration frameworks
• Contribute to architectural improvements by decoupling legacy dependencies and building modular, vendor-agnostic systems
• Participate in technical decisions involving identity management, data processing, and new platform features
• Lead code reviews, technical discussions, and knowledge-sharing sessions
• Mentor and collaborate with other engineers to support a strong engineering culture
• Support production systems through on-call rotations and incident response
• Enhance system health by improving test coverage, addressing technical debt, and refining operational processes

Requirements

• Minimum 5 years of professional software engineering experience
• Proficiency in Node.js/TypeScript and/or Go
• Experience with real-time systems such as WebSocket and event-driven architectures
• Solid understanding and practical experience with cloud infrastructure, preferably GCP and/or AWS
• Knowledge of microservices architecture and distributed systems with state management (e.g., ETCD, Redis)
• Working knowledge of MongoDB or similar document databases
• Experience building and maintaining RESTful APIs and event-driven systems, ideally with Kafka
• Strong system design skills considering scalability, latency, and failover
• Effective communication skills and ability to work in distributed, cross-functional teams aligned with CET timezone
• Preferred: experience with conversational AI, chatbot or voicebot platforms, NLP/NLU pipelines
• Preferred: familiarity with containerization and orchestration tools (Docker, Kubernetes)
• Preferred: knowledge of identity management systems (OAuth/OIDC)
• Preferred: background in CPaaS, scale-up, or fast-growth product companies