Backend Systems Engineer, Agent Infrastructure (mfx)

xHeron takes responsibility for guest operations for short-term rental businesses: guest communication coordinating teams resolving issues. Today that operating scope is delivered through a mix of people software and AI. Were building the technology to handle more of that work autonomously without turning into another tool customers have to supervise.

Were looking for a Backend / Systems Engineer to build the software that makes this reliable: persistent state safe execution permissions and recovery across humans agents and external systems.

What Youll Own

• Data models & state: Build backend services and data models that track operational work ownership and outcomes over time.
• Asynchronous workflows: Develop asynchronous workflows with reliable handling of retries timeouts external events and interrupted execution.
• APIs & tool execution: Build shared APIs and tool-execution interfaces including authorization and customer-data isolation.
• Knowledge infrastructure: Improve the infrastructure for storing versioning and serving operational knowledge.
• Platform quality: Strengthen testing and observability while evolving the existing platform alongside our CTO AI engineer and product engineering team.

What Makes You a Great Fit

• Strong backend engineering skills in Python and/or TypeScript/ with willingness to work across both.
• Practical experience with PostgreSQL or another relational database including data modeling and transactions.
• Experience shipping and maintaining production backend services.
• Familiarity with background jobs queues or event-driven processing and an understanding of failure handling and data consistency.
• The ability to investigate production problems design clear interfaces and deliver maintainable solutions.

Around 3 years of backend engineering experience is a useful guide not a hard requirement. The systems youve owned matter more than the number.

Nice to have: experience with workflow engines multi-tenant applications authorization FastAPI or agent tooling. Prior LLM experience is not required. Strong backend fundamentals and an interest in learning the agent domain matter more.

You May Not Be a Great Fit If

• You want to configure infrastructure not design the systems underneath it.
• You need a fully scoped spec instead of investigating ambiguous problems yourself.
• Youve never shipped and maintained a production backend service.
• You favor clever or complex solutions over simple maintainable ones.
• Youre looking for a defined 9-to-5.

Why Join xHeron

• Real ownership: youre working on foundational product architecture not cloud configuration with substantial technical ownership from day one.
• Direct founder access: youll work directly with our CTO shaping how humans and agents work together.
• We invest in our own: your ownership grows as the system does this isnt a role with a ceiling.
• Upside: VSOP alongside salary; youre building this with us.

Our Process

• Intro call (30 min): a conversation with Friedrich (CTO) about your background what youve built and why this role.
• Technical take-home case study: a short real engineering problem close to what youd actually be building.
• Case study interview (1 hour): you walk us through your thinking not just the final code.
• Culture fit (30 min): meet both Founders and make sure its a fit both ways.