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España
Remote only
Available
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.
Redesign, scale, and productionize an existing agentic system to support substantial user growth and real-world workloads.
Architect and operate the agent runtime, including orchestration, memory, verification, reliability, and other systems required for trustworthy AI workflows.
Own technical initiatives end to end across backend engineering, infrastructure, frontend development, and agent systems.
Establish the technical stack, engineering standards, development practices, and team norms as the first engineering hire.
Make high-impact architectural and technical decisions with significant autonomy and direct collaboration with the founder.
Deliver improvements and new capabilities on a frequent cadence, with software continuously shipped to real business customers.
Help shape the future engineering organization, including technical hiring and team development as the company scales.
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 early-career engineers are encouraged to apply.
Demonstrated experience building and operating LLM or AI agent systems in production, with real users depending on them rather than prototypes or side projects.
Strong full-stack capabilities, with the ability to work across backend, infrastructure, frontend, and AI/agent layers without relying on specialized teams.
Experience transforming working prototypes into reliable infrastructure capable of handling real production load, including architecture, data modeling, runtime design, and orchestration.
A track record of owning technical decisions independently as a founder, early engineering hire, or solo technical lead.
Strong founder mindset and a bias toward ownership, execution, experimentation, and building from first principles; previous founder or co-founder experience is a strong plus.
Experience with agent orchestration, agent memory, evaluations, verification systems, or multi-agent workflows is highly valued.
Familiarity with recruiting, agency, or service-delivery businesses is an advantage.
Strong computer science fundamentals are welcome, whether developed through formal university education or a strong engineering environment, but are not mandatory.
Based in Europe and genuinely open to relocating to San Francisco within the first year.
Annual salary of €80,000–€140,000.
Equity participation reflecting the founding nature and long-term scope of the role.
Fully remote work within Europe initially.
Relocation support for the move to San Francisco as the company establishes its U.S. presence.
U.S. visa sponsorship available from day one.
Direct collaboration with the founder and significant autonomy over technical direction.
Opportunity to grow into a CTO-level leadership position as the engineering organization develops.
Broad ownership across product, infrastructure, AI systems, and engineering culture.
