Senior AI Systems Engineer (Agents & Reasoning)

Mechanical design, the work done in CAD, is the rate-limiter for progress in the physical world. Despite decades of tooling, only a few million people can effectively design complex mechanical systems. But what if hundreds of millions could? What if creating something in the real world were as easy as imagining the use case, or sketching it on paper?

Backflip is building a foundation model for mechanical design. We are unifying the world’s scattered engineering knowledge into an intelligent software copilot. Makers and builders use our intuitive and effortless design environment to give them the superpower of expert mechanical design skills. Our goal is to enable anyone to imagine a solution and hit “print.”

Founded by a second-time CEO in the same space (first company: Markforged), Backflip combines deep industry insight with breakthrough AI research. Angel invested by Ashish Vaswani (coinventor of the transformer), and backed by a16z and NEA, we raised a $30M Series A and built a deeply technical, mission-driven team.

We’re building the AI foundation that tomorrow’s space elevators, nanobots, and spaceships will be built in. If you’re excited to define the next generation of hard tech, come build it with us.

We’re looking for a Senior Applied AI Engineer to design, build, and scale the agentic workflows within Backflip’s transformative products. You'll architect production-grade agent infrastructure moving well beyond simple API calls. You'll determine how we leverage multi-agent orchestration and tool-calling to help our mechanical engineering foundation model become a transformative tool for experts and laypeople alike.

You’ll create intuitive, high-performance mechanical design environments that connect human creativity to cutting-edge AI. Your work will directly shape how designers, engineers, and creators interact with our mechanical engineering foundation model, turning advanced AI capabilities into real, usable tools.

This is a hands-on, high-impact engineering role that blends traditional software engineering structured thinking with modern AI tools. We value proactive, product-minded engineers who can see the big picture while staying on top of the little details that define great products. You’ll be a key voice in the engineering team as we define the next generation of tools to create our physical world.

• You own a customer-facing product that is powered by an interactive AI workflow.

• You’ll connect the world of software and AI with the world of physical manufacturing (like 3D printers).

• Architect and build agentic systems and workflows, leveraging both our mechanical design foundation model and frontier models (OpenAI, Gemini, Claude, etc.).

• Establish rigorous evaluation practices, so all the customer sees is magic.

• Optimize agentic flows for speed and reliability.

• Contribute deeply to product direction: work with customers, design partners, the AI team, and leadership to new AI capabilities into transformative superpowers for our users.

• You’re pragmatic, product-minded, and enjoy owning features from concept to deployment. You enjoy being flexible and doing whatever it takes to achieve the mission.

• You have a strong command of programming in a modern language (we use Python and javascript).

• You have experience with LangChain, LangGraph, pydantic-ai, or equivalent orchestration frameworks.

• You have a solid grasp of agent architecture: tool/function calling, reasoning, multi-agent orchestration, agent loops

• You have hands-on experience with agent evals: trajectory evaluation, tool call accuracy, benchmarking

• You have experience integrating LLM-based systems into user-facing web products

• You operate with a leader’s mindset: set technical direction, create alignment and clarity with engineers and leadership, and deliver results.

• You are passionate about seeing your work shape the physical world.

• Ideally, you have experience with multimodal agents, not just text

• You have exposure to the world of mechanical engineering or related fields (aerospace, civil engineering, 3D printing, CAD, etc), e.g. through hobby builds, formal education, or prior professional work.

• Production experience with conversation memory, context window management, RAG, and memory summarization.

• You’re excited to work closely with a cutting-edge AI research team.

This is a rare opportunity to help define how physical AI becomes a tool for the imagination. You can build the interaction experience that puts the world’s collective mechanical design knowledge at anyone’s fingertips.

You’ll join a world-class, mission-driven team operating at the intersection of research, engineering, and deep product sense, building systems that let people design the physical world as easily as they imagine it.

Let’s build the tools the future will be made in.