This position is listed on behalf of a partner company, who manages all applications and next steps. Our partner is looking for a Founding Engineer based in Spain.

This is an opportunity to become the first engineering hire at an early-stage AI infrastructure startup with a working product and live revenue. You will work directly with the founder to shape the architecture, technical direction, and engineering culture from the ground up. The role centers on transforming a proven agentic system into production-grade infrastructure capable of serving up to a million users. You will have broad ownership across backend, infrastructure, frontend, and AI agent systems. With no engineering organization above you, your decisions will directly influence the product and future technical team. As the company grows, the role is expected to evolve toward a CTO-level position.

Accountabilities

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Redesign, scale, and productionize an existing agentic system to support substantial user growth and real-world workloads.

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Architect and operate the agent runtime, including orchestration, memory,



verification, reliability, and other systems required for trustworthy AI workflows.

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Own technical initiatives end to end across backend engineering, infrastructure, frontend development, and agent systems.

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Establish the technical stack, engineering standards, development practices, and team norms as the first engineering hire.

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Make high-impact architectural and technical decisions with significant autonomy and direct collaboration with the founder.

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Deliver improvements and new capabilities on a frequent cadence, with software continuously shipped to real business customers.

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Help shape the future engineering organization, including technical hiring and team development as the company scales.

Requirements

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At least 2 years of experience shipping production software, or an equivalent track record of building and launching real systems as a founder or solo builder; strong earl

📌 Founding Engineer (España)
🏢 Jobgether
📍 España