Senior AI Systems Engineer - Multi-Agent Systems

About the role

Merkle, a dentsu company, is looking for a full-stack engineer to build and deploy multi-agent AI systems at enterprise scale. You will design autonomous agent networks that solve real operational challenges, working across cloud infrastructure, backend services and AI frameworks, using Claude and modern AI tools to speed up development.

Key responsibilities

• Design and implement agent architectures with LangChain and LangSmith to orchestrate specialized agents for complex workflows.
• Build production backends in Node.js and frontends for human-agent interaction, using AI tools such as Claude and Cursor to ship faster.
• Deploy and scale agent services on AWS (EC2, Lambda, managed services) with hands-on deployment experience.
• Monitor agent behavior, token efficiency and latency with LangSmith, and implement fallback logic and state management for high task completion.
• Work with clients to define agent use cases, refine architectures and iterate on deployed systems.

Required profile

• Strong backend development in Node.js/TypeScript and comfort with frontends (React/Next.js).
• Practical, hands-on experience deploying and managing production workloads on AWS.
• Daily use of Claude, Cursor or similar AI coding tools, and experience with LangChain and LangSmith.
• Experience building or working with multi-agent systems (LangGraph, AutoGen, CrewAI or custom implementations).
• Ability to move quickly from concept to production and communicate with technical and non-technical stakeholders.
• Nice to have: experience with agent evaluation, self-correction loops or memory architectures; background in consulting or product studios shipping AI features; Python for specialized AI services.

What we offer

• 25 vacation days, plus 2 volunteering days and 3 extra wellness days.
• Health insurance (also possible for family members).
• Agile and flexible working hours, hybrid model with about 1 day per week in the office, and a digital nomad policy.
• Access to Dentsu Academy, career development focus and employee discounts.
• Team and company events, referral bonus program and free breakfast every second Wednesday of the month.