About the job
About Sim
At Sim, a dynamic startup backed by Y Combinator and supported by a $7 million Series A funding round led by Standard Capital, we are redefining the future of AI agents. Our tight-knit team operates out of San Francisco, collaborating in person each day to innovate and enhance our platform.
Our vision is clear: agents will shape the world, and Sim serves as the primary vehicle for this transformation.
About the Role
As a pivotal member of our team, you will spearhead the development of the Sim platform—the intuitive, end-to-end agent builder that empowers tens of thousands of developers daily. You will take charge of the front-end architecture, the real-time canvas, and the systems that transform visual flows into dependable, production-ready agents.
Dubbed the 'Figma for AI agents', Sim features an engaging drag-and-drop interface where developers can seamlessly connect LLMs, tools, APIs, and logic blocks to create intricate agentic workflows. Your mission is to enhance this experience, making it swift, enjoyable, and powerful enough that developers prefer it over traditional coding methods.
This foundational role entails defining the front-end architecture, establishing performance benchmarks, and refining developer ergonomics for a product embraced by over 70,000 builders. In our small team, you will have the opportunity to own the entire user interface that developers engage with.
What You'll Do
- Lead the design and development of the Sim visual canvas—the essential real-time, drag-and-drop workflow editor.
- Architect and implement front-end systems that visualize, connect, and manage sophisticated agent workflows.
- Devise the interaction model that enables developers to create, test, debug, and deploy agents visually.
- Bridge the gap between visual flows and the execution engine, ensuring seamless functionality.
- Enhance performance and responsiveness within the editor, even as workflows increase in complexity.
- Shape the developer experience and UX patterns throughout the platform, including block configuration, variable wiring, real-time feedback, and deployment processes.
- Collaborate across the stack within our Next.js monorepo, deploying updates to production daily.
- Establish front-end coding standards, including component architecture, state management, and testing methodologies.
What We're Looking For
- A design-oriented full-stack engineer with extensive experience in React and TypeScript.
- A strong sense of product design and user experience, with a focus on how interactions feel rather than just functionality.

