Founding software engineer - full stack (medior / senior)

Founding Software Engineer - Full Stack (Medior / Senior)

Stellar is an AI voice agent platform for customer support over the phone. We build systems that enable agents to operate alongside humans, handling a large portion of requests with minimal human intervention. This role is to join and help scale the platform as a founding engineer based in Amsterdam.

Our product distinguishes itself through:

• Remarkably human-like audio conversations at extremely low latency
• An intuitive agent editor interface for designing and iterating AI customer service agents
• An AI agent framework built for enterprise standards with safety mechanisms

We’re ambitious, product-obsessed, and laser-focused on solving real-world problems with trust, ownership, and impact from day one.

• Build performant, enterprise-grade APIs and backend services in Go and Typescript (Node.js)
• Develop Stellar's Studio frontend in React, TypeScript, and Next.js to enable companies to design, test, deploy and monitor AI voice agents
• Design a scalable, fault-tolerant system architecture for large volumes of real-time audio conversations with low latency
• Work on Stellar's AI agent framework at the intersection of software and AI engineering
• Design and implement a platform meeting enterprise standards for security, compliance, resilience and data privacy
• Build API integrations with customer systems (CRMs, support systems, internal APIs) to enhance agent capabilities
• Improve platform performance, observability, and developer experience to support a high-velocity engineering team
• Help shape early engineering culture and mentor future team members

• At least 4+ years of professional experience shipping software to production
• Comfortable with Go, Node.js, TypeScript and/or React (bonus to know all)
• Experience building across the full stack from frontend to backend to infrastructure
• Proactive, self-directed, and able to thrive in a fast-paced startup with autonomy

• You are a self-starter seeking ownership at a young, fast-growing company
• You enjoy working across the full technology stack
• You enjoy solving hard engineering problems at the intersection of software and AI engineering (low-latency voice infrastructure and enterprise-grade systems)

• Golang
• Typescript
• Node.js
• React
• Next.js
• Encore Cloud
• GCP

• Employment type: Full-time
• Seniority level: Mid-Senior level
• Job function: Engineering and Information Technology
• Industries: Software Development