Senior Java Developer - Barcelona

Wallapop

Wallapop is a Barcelona based scale-up driven by the purpose to empower people to embrace a more conscious and human way of consumption. We believe in a world where collaborative economy is mainstream. This is what drives us. 💫 Wallapop operates in Spain, Italy and Portugal, offering a catalogue of several hundreds of millions of products and services. Powered by technical innovation and continuous improvement, we bring together the scale & trust of classifieds with the marketplace’s convenience & reach. 🌱 Our mission is to enable a connected trade ecosystem, making 2nd-hand the norm through smart use of technology.   THE CHALLENGE 🧩 Are you ready to kickstart your engineering career? We are launching our first cohort of our Full-Stack Graduate Program—an immersive, 21-month rotational journey designed to cultivate adaptable, high-impact T-shaped software engineers.   At Wallapop, we believe in building solid vertical depth in a core technology while fostering a horizontal, working fluency across the rest of our ecosystem. Over the course of 21 months, you will complete three distinct 6-month rotations through our core engineering chapters—shipping real production code used by millions—alongside a 3-month business immersion rotation: * Backend Chapter (6 months): Deep dive into robust, scalable server-side systems using Kotlin & Java (with Spring Boot, Ktor, AWS, and microservices). * Frontend (Web) Chapter (6 months): Build responsive, elegant, and modern web applications using React & Angular. * Mobile Chapter (6 months): Craft exceptional native mobile experiences on either iOS (Swift) or Android (Kotlin/Java) depending on team fit. * Business Immersion (3 months): Step outside of engineering to complete a rotation in non-engineering departments. This will allow you to get to know other parts of the business and gain an understanding of how Wallapop operates as a whole.   You will be supported by a comprehensive, three-tier mentorship model including a dedicated Anchor Engineering Manager for your entire 21-month journey, a rotating Chapter Mentor for daily pair-programming, and a Rotation Team Manager to integrate you into cross-functional agile rituals. We also treat AI-native developer tooling (GitHub Copilot, Claude, etc.) as first-class citizens to help you ramp up and contribute fast! WHAT YOU WILL DO 👇 Build and ship features on systems used by millions of buyers and sellers — real work, not training exercises. * Rotate across engineering chapters over 18 months, gaining hands-on experience in Backend (Kotlin/Java), Frontend/Web (React/Angular), and one mobile platform (iOS or Android). * Rotation in a non-engineering department over 3 months. This will allow you to get to know other parts of the business and gain an understanding of how Wallapop operates as a whole. * Work with senior and mid-level engineers and cross-functional stakeholders who will mentor you, review your code, and push you to grow. * Use AI tooling as a first-class part of your workflow — Copilot, Claude, and similar tools are how we work, not an afterthought. * Participate fully in team life: standups, planning, retros, code reviews. * Own your learning — flag blockers fast, ask questions freely, and teach back what you're learning. WHAT WE’RE LOOKING FOR 🔎 We care more about how you think and learn than about what's on your CV. We're looking for people who are genuinely curious, who want to understand systems rather than just pass tests, and who are motivated by building things that matter. * Fresh graduate — University (e.g., UPC), Grado Superior, or equivalent. This is your first professional engineering role. * Basic coding fluency — you've built things, you can debug, you understand what your code actually does. * Curiosity — you ask why, not just how. * Learning velocity — you pick things up fast and lean into unfamiliar territory. * Openness to breadth — you're not here to be a one-stack specialist. You want to understand the whole picture. * Care — you want to do software well, for the right reasons. * Fluent English — Ability to communicate clearly and effectively with English-only stakeholders across Wallapop. WHAT WE OFFER 🚀 * Permanent contract from day one — you're an engineer at Wallapop, not a trainee on a clock. * 21 months of structured rotation with real ownership at every stage. * A dedicated mentor per chapter + a stable Anchor Engineering Manager across the full program. * AI-native onboarding — you'll be set up with the tooling and context to contribute fast. * A clear path to becoming a fully fledged Full-Stack Engineer at the end of the 21-month rotation. * Competitive graduate salary. * Wallapop's standard benefits package (detailed below!). Do note that all our jobs are 📍 Barcelona based. We follow a hybrid model where flexibility rules. We commit to a minimum of 6 days per month in the office. Each team self-organizes to decide on cadence and in-person/remote rituals. Wallapop is an equal opportunity employer. We celebrate diversity and are committed to creating an inclusive environment for all employees as we want Wallapop to be a place for everyone. Additionally to the opportunity to contribute to an agile product set up and work together towards achieving our meaningful mission, we offer the following 🍭 Perks & Benefits: * Generous individual learning budget of 2k per year * Free office meals, lunch selection from different providers * Group and individual English, Catalan & Spanish lessons as part of our working day * Private Health Insurance with Alan * Flexible working hours + Intensive Fridays * Flexible remuneration to deduct from gross salary (kindergarten/food/transport check) * Gym & Wellness plan, including physiotherapist in the office * Generous referral Program & Charity Donation * Bonus for weddings & newborns * Wallapop Renta (Tax income support) * Monthly plan for free shipping, bumps & home-pick-up on our services * Work anniversary Gifts and Birthday Surprises * Contribution towards your WIFI in your monthly payroll * One-off payment based on compensation package to go towards setting up your home office * Relocation package (monetary support and legal advice) and visa sponsorship, if applicable * 26 holidays per year * TOP hardware of your choice (latest Apple or Windows)   What does the hiring process for this position look like? 👀 Intro Call - run by talent acquisition, focus on providing more information about the role and the company as well as going over your experience, motivation, and expectations. This usually takes 45-60 minutes. Conversation with an Engineer: In this step, you will meet with a member of our engineering team. We will dive deeper into your technical background and problem-solving approach to assess if you are a strong fit for the team. It is also a great opportunity for you to ask specific questions about our tech stack and the day-to-day work. In-Person Assessment Centre (Mid-September): If selected, you will be invited to our office for a collaborative assessment centre. You will participate in exercises alongside other candidates, giving you a chance to showcase your skills, meet our team, and get a real feel for how we work.

Sumup

About SumUp We believe in the everyday hero. Small business owners are at the heart of all we do, so we're creating tools that help them run their businesses. With a founder’s mentality and a 'team-first’ attitude, our diverse teams across Europe, South America and the United States work together to ensure that the small business owners we partner with can be successful doing what they love.  Team Description The Lending team offers a fair, easy, timely, and financially relevant lending experience to small merchants. Empower small business owners to manage their financing independently of the stage of their business, either funding their growth, managing their cash flow, or covering their operational costs. Enable capital to be available to our merchants and consumers, always and everywhere. We are looking for our new Senior Engineer for our team responsible for developing and maintaining the backend two important pieces of our products: Risk Assessment and Dunning & Collection. This includes designing, implementing, and testing new features, as well as improving the performance and scalability of existing ones. What you’ll do * The goal is to improve the functionality and user experience of SumUp's lending platform and to ensure that it meets the needs of our merchants. * Design and develop Risk Assessment and Dunning & Collection micro-services, considering differences between markets; * Improve the performance and scalability of the systems; * Design and develop integration with external partners to enable growth. * Contribute to the development of a high-performing team. You’ll be great for this role if * More than 4 years of experience as a Software Engineer * Experience with Golang or other OOP languages such as Java, Kotlin, Python, etc.  * Experience in creating and maintaining simple components in React. * Experience with RESTful API design and development. * Experience with Git and Git workflows. * Experience with SQL and NoSQL databases, such as PostgreSQL It will be an awesome add * Good English communication skills to engage in technical refinements with an international team * Experience in a fintech/startup environment Why you should join SumUp * Opportunity to work with a truly global, multicultural team (we are 3000+ people from 93 countries, spread across 4 continents). * Learning & development budget for attending conferences and external training * Competitive salary package and virtual stock option program * Office relaxation activities such as yoga and massages regular brunches, football events, and office parties * 23 days paid vacation days * Additional health insurance and Multisport card * Restaurant ticket * An amazing team and work environment that works with passion and purpose to achieve incredible results SumUp is an Equal Employment Opportunity employer that proudly pursues and hires a diverse workforce. SumUp does not make hiring or employment decisions on the basis of race, colour, religion or religious belief, ethnic or national origin, nationality, sex, gender, gender identity, sexual orientation, disability, age, or any other basis protected by applicable laws or prohibited by company policy. SumUp also strives for a healthy and safe workplace and strictly prohibits harassment of any kind. SumUp will not accept unsolicited resumes from any source other than directly from a candidate Job Application Tip We recognise that candidates feel they need to meet 100% of the job criteria in order to apply for a job. Please note that this is only a guide. If you don’t tick every box, it’s ok too because it means you have room to learn and develop your career at SumUp.

FREENOW

Location: Come and join us in Barcelona! We are looking for a talented and motivated Senior Backend Engineer (m/f/d) for our new Driver Onboarding team. As part of a highly skilled, cross-functional team comprising Fullstack Engineers, Backend Engineers, a Product Manager, a Product Designer, a Data Analyst, and a technical Engineering Manager, you will help shape the future of mobility with FREENOW and assist our drivers in their daily work. Our team is the cornerstone of the driver experience, with a core focus on streamlining the driver registration flow and ensuring the integrity of our platform through advanced document validation processes. Our mission is to provide a fast, frictionless, and secure onboarding journey for every new driver. We achieve this by: * Designing and implementing the entire driver registration and onboarding journey, making it simple, intuitive, and fast. * Developing and maintaining robust, automated document validation systems, powered by LLMs and ML models, to ensure compliance and quick approval for drivers. * Collaborating closely with Operations and other engineering teams to constantly optimize process automation within the document lifecycle. * Providing self-service tools that empower drivers to efficiently manage their documentation and account details. * Integrating key insights into internal systems, fostering collaboration across teams to improve the overall driver experience. As a critical part of our company, this team's work directly impacts thousands of drivers and, ultimately, the experiences of millions of customers. Your contributions in this role will have a tangible and far-reaching effect on the lives of many. As an engineer on our team, you will tackle the exciting challenges of building a best-in-class driver onboarding platform. This includes designing and building innovative, high-scale solutions for document validation and workflow automation, directly enhancing the start-to-finish experience for our drivers and ensuring the quality and compliance of our fleet. You'll be involved in every stage of product development, from ideation to implementation, ensuring a seamless and impactful experience. We also value a mindset that challenges the status quo—constantly exploring new technologies and approaches to improve our products and maintain a state-of-the-art codebase. Beyond technical excellence, your contributions will help foster a collaborative and inspiring team culture, making our workplace an enjoyable and fulfilling environment. ---------------------------------------------------------------------------------------------------------------------------------- YOUR DAILY ADVENTURES WILL INCLUDE: * Own the Feature, Own the Code – feel responsible for what you create. It all starts with bringing in your feature ideas, goes over development, testing and ends in deploying your code and monitoring it. * Design and develop systems based on product requirements or refactorings. * Maintain and improve the existing systems by finding bottlenecks and performance issues and improving resource usage (DB access, cache, messaging, etc.). * Collaborate with your team members in an Agile environment, contribute to and live our agile ceremonies. * You care about teamwork: Be accountable for all topics above, but work together with the team on them. * Stay on top of the latest technology trends and AI-assisted development tools, and bring best practices to our daily work. Our Techstack: Kotlin | Java | AWS | Docker | Git | Kafka | ElasticSearch & more ---------------------------------------------------------------------------------------------------------------------------------- TO BE SUCCESSFUL IN THIS ROLE: * Passionate about Kotlin or Java. * Experience with the quirks of Spring Boot or similar frameworks, automated tests and CI/CD tools. * Knowledge of microservices architecture. * Comfortable with AI-first development practices, we use tools like Claude and Cursor daily, so experience or strong interest in AI-assisted coding is important. * Familiarity with monitoring tools (i.e., Grafana, Datadog, Kibana etc.). * Keen about principles and practices of scalable web applications, such as RESTful API’s, dealing with transactions, and resiliency. * Familiar with messaging by using Kafka or RabbitMQ. * High level of creativity; there’s all the freedom to think outside the box. * Be communicative, proactive, and always collaborative. * Excellent written and verbal communication skills in English. Nice to have:  * Experience working with AWS or similar cloud service providers. * Experience in Python, particularly for data processing or AI integration tasks. * Experience with document automation validation. * Familiar with Agile methodologies such as Scrum or Kanban. ---------------------------------------------------------------------------------------------------------------------------------- BENEFITS & PERKS IN A NUTSHELL: * Flexible working arrangements * LinkedIn Learning * Sabbatical & special leave policies * WeRoad partnership * Birthday, 24th + 31st December off * Short term EU work policy * Mobility Credit * Health Insurance * Employee assistance program   ---------------------------------------------------------------------------------------------------------------------------------- DIVERSITY, EQUITY & INCLUSION: FREE NOW is an equal opportunity employer and we consider qualified applicants regardless of race, religion, national origin, gender, gender identity, sexual orientation, disability or age. We want you to grow and evolve, bring your true self to work. ABOUT US: Freenow by Lyft empowers smarter mobility decisions, helping people to move freely and cities to thrive. Through our multi-mobility app, we feature broad options for everyone across 9 European markets and over 180 cities. Millions of passengers can access services including taxis, private hire vehicles, carsharing, car rental, e-scooters, e-bikes, e-mopeds, and public transport within a single app.  In July 2025 Freenow was acquired by Lyft, a global mobility platform, which connects riders and drivers for billions of rides across North America and Europe. Together, Freenow and Lyft are creating a more caring and connected world, with transportation for everyone. We are a global, diverse, highly motivated, and collaborative team that strives for excellence and likes to have fun. Ready for your next ride? ---------------------------------------------------------------------------------------------------------------------------------- SEE WHAT OUR AWESOME COLLEAGUES SAY ABOUT US:                 ----------------------------------------------------------------------------------------------------------------------------------