YC Work at a Startup - On-site work

Join Channel3 as a Fullstack Engineer in New York to build the definitive internet product database. You'll leverage Python, TypeScript, and React to shape merchant-facing tools and pioneer agentic commerce UX. This role offers ownership of frontend architecture in a fast-paced environment with t...

Join mcp-use to build leading open-source dev tools for the Model Context Protocol (MCP). Develop the premier platform for deploying MCP servers and agents, enhancing our popular SDK used by NASA, SAP, and 5,000+ companies. We seek a brilliant, high-agency software engineer passionate about LLMs ...

Join Hypercubic as a Founding Software Engineer in San Francisco. Shape AI systems that analyze and rearchitect critical legacy enterprise applications. You'll work directly with the CTO, owning architecture and product direction from prototype to production. This role demands strong fundamentals...

Join as a Founding GPU Kernel Engineer in San Francisco. Hand-tune and optimize low-level GPU kernels for ML workloads, pushing hardware limits. Deep expertise in CUDA/ROCm, profiling tools, and GPU assembly is essential. Receive equity, bonus, benefits, and relocation assistance in this pivotal ...

Join as a Founding Engineer to architect the Unity mobile app for Pax Historia from scratch. You will build the core gameplay loop, optimize for mobile performance, and integrate with backend services. This role requires 3+ years of experience shipping polished Unity apps to iOS/Android stores. B...

Join Truth Systems as a Founding Full-Stack Engineer in San Francisco. You'll build our core trust & safety platform from 0→1 using React, TypeScript, Next.js, and Python. We seek a product-focused, empathetic builder with strong full-stack skills. Receive meaningful equity (0.3-1%) and comprehen...

Join Verne as a founding Robotics Data Infrastructure Engineer in San Francisco. Architect and deploy critical AWS and edge data pipelines for real-world robots. You'll manage large-scale multimodal datasets and build MLOps tooling, directly impacting production systems. Requires strong Python, A...

Join Idler in San Francisco as a Software Engineer. Build agentic systems and tooling for cutting-edge AI coding environments used by leading labs. We seek passionate developers, including new grads (US only), to ship features fast. Enjoy full benefits, latest tech, PTO, and team events.

Join FLEETLINE as a Founding Algorithm Developer in NYC. Build and scale core optimization algorithms (MILPs, ML, RL) for large trucking companies. We seek a versatile Python/TypeScript engineer who ships code fast, thrives in ambiguity, and works directly with customers. This is an in-office rol...

Join Uplane as a Founding AI Engineer in San Francisco. Build the core AI engine for automated marketing using LangGraph, TypeScript, and PostgreSQL. Own projects end-to-end in a fast-paced, well-funded startup. Visa sponsorship is available for this on-site role.

Join Uplane as a Founding Full-Stack Engineer in San Francisco. Build our core AI system using TypeScript, Node.js, and Nuxt/Vue with PostgreSQL. Be a key early employee, own the product lifecycle, and solve a massive problem in marketing tech. We offer visa sponsorship for this on-site role.

Join as a Founding Product Engineer in San Francisco. Own the full user-facing platform, from polished React/Next.js interfaces to robust backend services. You'll ship complete products, leveraging AWS/Kubernetes, with a sharp eye for design. Receive equity, benefits, and relocation assistance.