Labhouse is a Barcelona-based startup studio building AI-powered mobile apps used by hundreds of thousands of people worldwide. Our products — including Invoice Fly and Summary AI — are designed to make everyday tasks faster, smarter, and simpler through a subscription model that puts the user first.

We were founded by Andrés Bou and Horacio Martos, the duo behind SocialPoint (acquired by Take-Two Interactive), and we operate with the mindset of a product company: small teams, high ownership, and a relentless focus on building things that matter.

We're now looking for a Lead Backend Engineer to own one of our most technically ambitious greenfield projects — and eventually grow a team around it. 🚀

About the Role

We're building something new in-house — a greenfield backend system that sits at the intersection of mobile, data, and growth infrastructure. The details are under wraps for now, but the challenge is real: you'll design and build this from scratch, with full ownership over the architecture, the stack, and the technical decisions.

You'll start as an IC, then grow a team around what you build.

What you'll do:

• Architect and build a complex, high-scale backend system from the ground up — greenfield, no legacy constraints

• Choose and own the technology stack; we're open to the right tool for the job

• Design reliable, low-latency data pipelines and the APIs that power the product

• Work closely with Growth and Product teams to ensure the system delivers the right data for decision-making

• Lay the technical foundation with future team growth in mind — your architecture decisions will shape how this team scales

About You

Academic Background:

• You hold a degree in Computer Science, Software Engineering, or a related technical field. Strong academic foundations in distributed systems, data engineering, or backend architecture are a plus.

Technical expertise:

• 7+ years of backend engineering experience, with a strong track record of building complex, high-scale systems from scratch

• Experience working on data-intensive backend infrastructure: event pipelines, distributed systems, high-throughput APIs

• Strong backend fundamentals — you can pick the right architecture for the problem, not just the one you know best

• Experience working with TypeScript/Node.js is a plus, but we're open to other languages — stack is not closed

• Proven ability to work autonomously and make sound technical decisions without heavy oversight

• A builder's mindset: you're energized by the blank-page challenge of creating something from zero

Communication

• You communicate clearly and proactively — whether it's aligning with the Growth team on attribution requirements, documenting architectural decisions, or flagging blockers early.

• You're comfortable working remotely and know how to stay connected and collaborative across an async environment.

Nice to Have

• Prior experience at a mobile-first company or ad tech company, especially in growth or data infrastructure

• Familiarity with the mobile measurement ecosystem — knowing how these tools work helps you build better

• Experience with fraud detection in data pipeline contexts

• Experience hiring or mentoring engineers — you'll be doing this soon

What We Offer

• Competitive salary, attractive and above market average

• Remote work from anywhere in Spain. If you are based in Barcelona, we would love for you to join us at the office (Barcelona Tech City) at least two days a week.

• The chance to build a technically complex system from zero, with full ownership

• A lean, high-talent environment where your work has direct and visible impact

• Work alongside founders who have built and scaled globally successful products

Hiring Process

1. TA Interview – Initial conversation to get to know each other and understand your background.

2. CTO interview – Deep dive into your product thinking, experience, and fit with the team.

3. Technical Case – Practical exercise to assess your product, analytical, and strategic capabilities.

4. Final Interview – Final conversation to ensure alignment on expectations, culture, and role fit.

You should Know:

Labhouse is proud to be an equal-opportunity employer. However you identify or whatever your journey to this point, we welcome all candidates to apply for the position that inspires them.

Come join us and help us build a company that everyone is proud to be part of.