Founding Software Engineer

Join Hire Hangar and work with fast-growing global companies while building a long-term, remote career. Job Title: Founding Low-Level Software Engineer Location | On-Site — San Francisco, CA Time Zone | PST Role Overview: We are seeking a Founding Low-Level Software Engineer to join an early-stage AI video infrastructure startup. The company's first product turns prompts and documents into whiteboard-style explainer videos in seconds, working toward a bigger vision of making video generation as fast, cheap, and programmable as text is today. As one of the first engineering hires, you will focus on the deep technical work that keeps the product fast and efficient at scale — profiling bottlenecks, tuning resource usage, and building clean abstractions around genuinely complex internals. This role is a strong fit for someone who enjoys working close to the metal and has a track record of measurable technical impact. Key Responsibilities: - Improve speed, efficiency, and reliability across core technical systems - Profile and resolve bottlenecks in code, media pipelines, and infrastructure - Build tooling for benchmarking, testing, and tracking system regressions - Tune concurrency, caching, batching, and scheduling for better resource use - Design clean internal interfaces that hide complexity from the rest of the team - Stay close to product priorities while solving deep technic...