About Winsen Labs
Winsen Labs is the lab behind Winsen One, Walle, Platos and Rocketman. We build AI for financial services, manufacturing, logistics and healthcare: systems that own real operational work end to end, at full volume, with every action logged and a human signature on anything that counts. The agents you will build here carry that same standard into enterprise workflows.
The role
We are hiring a founding engineer with an AI + backend bent to build durable AI agents for financial and enterprise workflows.
This role combines backend engineering, applied AI, and forward deployed engineering. You will build agent infrastructure, run evals, create reusable harnesses, and work directly with customers to turn real workflows into production systems.
You will work across orchestration, state management, tool execution, APIs, background processing, observability, integrations, and deployment.
The role is for engineers with one to two years of experience, or exceptional new grads with strong portfolios. We care more about technical ability and what you have built than credentials or years of experience. Strong GitHub work, OSS contributions, production systems, research, and serious side projects all matter.
Who you are
- Strong backend fundamentals. Comfortable with APIs, databases, queues, concurrency, retries, caching, state, and observability.
- Applied AI experience. Familiar with LLMs, agents, tool calling, structured outputs, retrieval, memory, and orchestration.
- Strong on evals. Comfortable building evaluation datasets, regression tests, traces, and failure analysis workflows.
- Customer-facing. Able to understand messy business processes, ask the right questions, and translate them into technical systems.
- Systems-oriented. You think about reliability, scale, failure modes, and architecture, not just feature implementation.
- Strong builder profile. Good GitHub, OSS contributions, technical projects, or evidence of shipping meaningful systems.
- Curious and high ownership. You learn quickly, go deep when needed, and can make progress without detailed instructions.
- AI-native developer. Comfortable using tools such as Cursor, Claude Code, Codex, Copilot, or similar systems as part of your development workflow.
What you will do
- Build backend services for Winsen Labs' agent platform
- Build durable, stateful, long-running workflows
- Design reusable harnesses for financial and enterprise use cases
- Run evals and build regression testing infrastructure
- Build tool execution, integrations, and background processing
- Add tracing, replay, logging, and monitoring
- Work directly with customers from discovery to deployment
- Improve reliability, performance, and scalability
- Contribute to core technical and architectural decisions
Hiring process
- Application review. Resume, GitHub, OSS work, and projects reviewed using automated screening and human review.
- Intro call, online. Non-technical conversation to understand your background, interests, and working style.
- Take-home assignment. Practical engineering exercise.
- Technical interview, online. Discussion around the assignment, backend fundamentals, AI systems, and engineering decisions.
Why Winsen Labs
You will join early, own meaningful systems, work closely with customers, and have direct influence on product and architecture.
How to apply
Hit Apply for this role below. Link your GitHub and anything you have shipped, attach your résumé, and tell us about the work you are proudest of. Short and true beats long and polished.