Barcelona, Spain — hybrid
Full-time employment
0.5–1% equity About Our Client Our client is an early-stage technology company building an AI-native platform for complex hardware engineering.
The platform brings system architecture, requirements, verification, engineering workflows, and technical decisions into one traceable environment. It provides engineers and AI agents with the context required to design, validate, and evolve complex hardware systems more effectively.
The company is now preparing for its next stage of growth, including a planned seed funding round in autumn 2026.
The team currently consists of two founders supported by an external engineering team. This hire will become the first senior technical leader brought fully in-house.
About the Role Our client is looking for a deeply hands-on software architect who can become the technical reference point for the product and the future engineering team.
You will work directly with the founders, take ownership of the existing architecture and production environment,



and gradually assume responsibility currently held by an external software architect.
You will spend most of your time designing, building, reviewing, debugging, and shipping production software.
You will also own the decisions behind the implementation: how services and data models should be designed, which technologies are appropriate, where strong foundations are necessary, and where a simpler solution is better.
Design and evolve the backend architecture, APIs, and relational data model
Build product capabilities across backend, frontend, infrastructure, and AI systems
Review code in depth and maintain ownership of technical quality, including AI-generated code
Define practical standards for architecture, testing, security, observability, releases, and documentation
6–10 years of professional software engineering experience
~ Strong hands-on experience owning production software systems
~ Particular depth in backend architecture and relati

📌 Front-end Software Architect (Cataluña)
🏢 OnHires
📍 Cataluña