Founding Engineer

Company Description Lightsage (formerly Sapient) builds infrastructure for the emerging agent economy, helping organizations track, benchmark, and improve how coding agents discover and use their APIs, CLIs, and MCPs. The company enables enterprises and high‑growth startups to become the default tools recommended by agents, focusing on agent experience, discoverability, and performance. Lightsage is behind DevToolArena.com, a public benchmark platform that ranks developer tools across authentication, inference, voice, and more using systems like Claude Code and Codex. Role Description As a Founding Engineer at Lightsage, you will design, build, and scale core infrastructure and products that power agent‑led growth for developer tools and platforms. You will work closely with the founders to define technical architecture, implement new features, and create benchmarks and analytics that measure how agents interact with APIs, CLIs, and MCPs. Your day‑to‑day will include writing high‑quality production code, building data pipelines and dashboards, integrating with third‑party tools, and experimenting with agent frameworks and AI coding systems. You will collaborate directly with customers to understand their needs, refine product requirements, and ship end‑to‑end solutions from prototype to production. Requirements Able to take a loosely defined customer or product problem and drive it to a working shipped solution Prior founder or early‑stage startup operator experience is a plus Strong written communication and ability to explain technical decisions clearly This is a full‑time, on‑site role based in San Francisco, CA, with significant ownership, autonomy, and impact on the company’s technical direction. #J-18808-Ljbffr