Circle is building the world's leading AI-powered, all-in-one platform for digital businesses. We make it possible for creators, coaches, educators, and businesses to bring together their audience with engaging discussions, live streams, events, chat, courses, and payments — all in one place, all under their own brand.
We're proud to be a fully remote company of around 270 (and growing) Twice a year, we bring the whole company together in beautiful places around the world for our company offsites. The AI Quality engineering team at Circle owns the foundation for measuring, diagnosing, and improving the quality of Circle's AI-powered features. This team focuses on building the infrastructure to measure, diagnose, and improve production AI systems, rather than ML research or model training.
We're looking for a Lead Engineer to help us build out the evaluation frameworks, observability tooling, and diagnostic infrastructure that tell us whether our AI Agents are working well, where to improve them, and how to make them faster and more cost-efficient.
You'll also lead and manage the AI Quality engineering team, with an ambitious and growing roadmap.
Diagnose exactly where quality breaks down. Evaluate new and open‐source models against our production baseline, build the framework we use to decide when to shift models, and chase cost and latency wins through model swaps, caching, and routing by plan complexity.
Lead and grow the AI Quality engineering team. Work with the engineers building Circle's AI products so they have real confidence that their changes are actually improving quality, not just shipping.
7+ years of experience building and shipping production software, ideally including LLM‐powered agents that take real actions in a product. You've worked on complex, tool‐using systems (multiple tools, planning or orchestration, sub‐agents) not just simple, single‐turn assistants, and you can walk us through something you shipped and how you knew it was actually worki
📌 Lead IT Developer (Madrid)
🏢 Circle
📍 Madrid