About Tree-Nation Tree-Nation is the world's largest reforestation platform, connecting citizens and companies with verified planting projects across the globe.
Since **, over 800,000 users and 30,000+ companies have planted more than 45 million trees through our platform, across 40+ active reforestation projects worldwide.
We combine technology and environmental impact to make reforestation simple, transparent, and scalable.
Our goal is to plant 1 trillion trees by ** — and we are building the platform, the automation, and the systems to get there.
The Team — What We Are Made Of Our team spans many nationalities, backgrounds, and disciplines.
What we share is a mindset: we take ownership because we care about what we're building, we don't back down from hard problems, and we trust each other to lead, make decisions, and ask for help when needed.
We are investing heavily in automation and AI to scale our impact.
The company provides access to the latest LLMs, and we strongly encourage everyone to innovate.
We're based in Barcelona and work primarily from the office, because the energy of working side by side matters to us.
About This Position We are looking for a senior product builder to join Tree-Nation's tech team.
This is not a classic PM role.
There is no CPO layer above you, no product team around you, and no process handed to you.
You will work directly with the CEO and the engineering team to turn business vision into clear, coherent, build-ready product features — and you will own that function end to end.
The profile we're looking for sits at the intersection of three things: product ownership, technical depth, and business judgment.
All three are non-negotiable.
You need to think like a product owner — flows, specs, UX, priorities,



quality.
You need to think like an engineer — data models, service boundaries, backend logic, implementation trade-offs.
And you need to think like a businessperson — commercial impact, revenue logic, what's worth building and what isn't.
Tree-Nation is a complex platform: planting logic, sponsors, users, forests, credits, billing, reporting, integrations, automation, operational tools, and environmental data all need clean domain separation, strong data models, and well-defined interactions.
Your job is to bring clarity to that complexity — from first principles, not from templates.
This role is for someone who has operated in small, unstructured environments and thrived.
We are looking for a rare generalist: part product owner, part systems thinker, part technical generalist, part creator — with strong product judgment, business sense, UX/design taste, and the ability to turn complex ideas into simple, scalable product solutions.
Someone able to start from a blank page, move without being told, and take full ownership of the product agenda without anyone managing it for them.
What You'll Do Turn business vision into build-ready product features, flows, specifications, and roadmap decisions Apply business judgment to every product decision — understand the commercial impact, the revenue logic, and the tradeoffs between speed, quality,



and scope Design product logic from first principles: entities, data models, states, permissions, rules, edge cases, service boundaries, and acceptance criteria Work directly with engineers as a technical peer — not as a translator or ticket manager, but as someone who understands the system deeply enough to challenge, contribute, and decide Validate finished work deeply: product QA, edge cases, data logic, user experience, reporting, billing, credits, sponsor logic, and operational impact Identify weak product logic early, especially unclear ownership, poor domain separation, fragile data structures, unnecessary exceptions, or scalability issues What You'll Bring Required 10+ years of experience in tech, product, systems, engineering, technical product management, product ownership, or a hybrid product/engineering role Exceptional system-design ability: databases, APIs, backend logic, entities, relationships, permissions, states, business rules, service boundaries, data ownership, and implementation trade-offs Strong database and data-modeling skills — you naturally think in tables, entities, states, relationships, rules, constraints, ownership, interfaces, and consequences Experience working in small teams in a startup or early-stage environment — you've had to wear multiple hats and operate without infrastructure Proven ability to work from a blank page — you've designed systems, flows, and product logic from scratch, not just improved existing ones Ability to read and understand code well enough to follow product logic, discuss implementation with engineers, and detect technical or architectural problems Ability to write clear, technically coherent product specifica

📌 Senior Product Builder (España)
🏢 Tree-Nation
📍 España