Growth Intern

We welcome applications year-round for both shorter internships and gap-year internships.

About Seventh WaveSeventh Wave is part of Adevinta, one of the world’s leading online classifieds groups. We’re a small, exceptionally talented team at the frontier of AI deployment, pushing the boundaries of how classifieds businesses operate at scale. We build, shape, and run these businesses end-to-end, driven by an owner-founder mindset from day one. Joining us now means joining early and having a direct hand in shaping our growth journey.
Across Adevinta, our marketplaces reach more than 100 million users every month. Backed by an investor consortium including Blackstone, Permira and General Atlantic, the group brings together leading marketplaces such as mobile.de and Kleinanzeigen in Germany, leboncoin in France, Marktplaats in the Netherlands, Subito in Italy and Kijiji in Canada.

Why join us
We are building a small team of exceptional people early in their careers who want to build, take responsibility and grow with the business.

Own meaningful work from the start. Take responsibility for a defined assignment that contributes to a live commercial initiative. You'll work with a growth manager and local teams, with guidance as you put your ideas into practice.
Learn from experienced operators. Work alongside growth managers and marketplace teams, with opportunities to learn from experienced business leaders. Regular feedback will help you develop your commercial judgement and practical skills.
Build a foundation for your career. Learn how marketplace businesses grow by contributing to real projects. As you develop, you'll have opportunities to take on more responsibility within your assignments.
Put AI to work at marketplace scale. Help apply AI to customer experiences, growth campaigns and commercial workflows. You'll work with the team to test ideas, measure their impact and put useful approaches into practice.
Build repeatable capabilities. Help turn what works in our starting markets into playbooks and shared capabilities that other marketplaces can use. You'll work with teams across countries to adapt and implement them, extending the impact of your work across the group.
Help build Seventh Wave from the start. Contribute ideas and help improve how we work as Seventh Wave grows. You'll be part of a team being built from the ground up, with the backing of an established group.

Responsibilities

You'll own a defined piece of commercial work, with guidance from a growth manager and direct exposure to the teams running our marketplaces.

• Own a meaningful assignment. Take responsibility for a defined project, such as customer research for a new business model or a campaign test that guides investment, with support from a growth manager.
• Find growth opportunities. Research customers, competitors and market trends, and turn your findings into recommendations the team can act on.
• Answer questions with data. Analyse user, product and commercial data to answer a specific business question, working with growth managers and analysts to check your findings.
• Help bring ideas to market. Prepare propositions, campaign materials or tests, then support their launch and use the results to recommend what to do next.
• Improve everyday work with AI. Test AI tools in research, analysis or campaign preparation and develop useful approaches you can share with the team.
•  Make good work reusable. Capture successful methods and results in templates and playbooks, and help other marketplace teams adapt them.

Requirements

About you

• Clear thinking. You break unfamiliar questions into manageable parts and explain your reasoning clearly. You ask useful questions and revise your view when you learn something new.
• Drive and ownership. You set yourself demanding goals, take initiative and follow through on commitments. You raise problems early and act on feedback to improve.
• Analytical rigour. You turn a question into a simple analysis, explain your assumptions and check whether the numbers support your conclusion. You're comfortable with spreadsheets and careful with the details.
• Curiosity and learning. You pick up new topics quickly and experiment with AI and other tools to find better ways of working.
• Teamwork and communication. You communicate fluently in English, ask for help when needed and keep colleagues informed. You welcome feedback and contribute to the success of the team.
• Evidence of potential. You have achieved strong results through studies, internships, projects or something you built yourself. What matters is the quality of your work and the initiative behind it.

Benefits

Location. We work in person at our Barcelona office, with occasional travel to our marketplaces depending on your role and scope.
Development. Hands-on experience across commercial topics, with regular feedback and guidance from experienced colleagues.
Environment. An international team with high standards, meaningful responsibility and support as you learn.

Our application process
We look for evidence of clear thinking, initiative and follow-through. Our case studies reflect the practical decisions and commercial challenges you would work on here. We'll explore how you approach unfamiliar problems, make decisions and turn them into action.

1. Apply. Send us a one-page CV and a one-page cover letter. Tell us why you want to join Seventh Wave, what you would bring to the team, and your preferred start date and internship duration.
2. Application review. Our hiring committee reviews every application personally and will be in touch within two weeks.
3. Shortlist and next steps. If we shortlist your application, we'll share the interview format, who you'll meet and any preparation required.
4. Two interviews. You'll meet the team in two interviews combining personal fit discussions and practical case studies. We'll explore your motivation, how you approach problems and how we would work together, with time for your questions throughout.