Fullstack Product Engineer (Learn & Agents)

At Hemnet, we build one of Sweden’s most widely used digital services. Every day, we help people navigate some of life’s biggest decisions, and that brings high expectations for quality, reliability, and long-term thinking. We’re now looking for a Fullstack Developer to join our B2B & Seller Domain. This team builds products and services that help homeowners and agents make the most of their opportunities in the housing market. About the role 🍏 You’ll be part of an experienced, cross-functional team working across both user-facing features and backend systems. You’ll contribute through hands-on development, technical leadership, and close collaboration with Product Managers, Designers, Analysts, and Engineers. Together, you’ll build solutions that create real value for sellers. You’ll design, build, and maintain scalable backend services using Ruby, Node.js and Nest.js, contribute to frontend development in React, and support and evolve APIs across GraphQL and REST. You’ll also play an active role in our transition toward a more service-oriented architecture, helping break down complex problems and move monolithic systems into modular services over time. Beyond day-to-day development, you’ll take part in technical discussions, contribute to architectural direction, support other engineers through collaboration and knowledge sharing, and help us continuously improve code quality, performance, and developer experience. We also hope you’ll contribute to a team culture where different perspectives are valued and people can grow together. Who we think you are 🤩 Our current stack includes Ruby and Node.js on the backend and Next.js on the frontend. You’ll work with Ruby in this role, but we don’t expect you to know everything from the start. We think you’re an experienced engineer who enjoys building production-grade systems and working through complex problems together with others. You care about code quality, maintainability, and creating solutions that hold up over time. You’re comfortable contributing to technical decisions, and you like collaborating across disciplines to build products that are useful and thoughtful. You don’t need to tick every box on day one, what matters most is that you bring solid engineering experience, a learning mindset, and a generous way of working with others. What you’ll do 💥 * Build and improve Hemnet’s products across the system. * Take part in technical discussions and architectural decisions * Work closely with product, design, and analytics. * Contribute to a sustainable pace, high quality, and a great developer experience. * You’ll use AI tools as part of your day-to-day work, for example to explore ideas, speed up implementation, improve code quality, and support learning and collaboration across the team. I am your new manager 👋 Hi! My name is Tomas, and I’ll be your new manager. I’ve been at Hemnet since 2022 and am currently working as Engineering Manager in our domain called B2B & Sellers. I’m really excited to support the teams that will be working on many new and important areas for Hemnet, including building tools and products for agents to help them make more informed decisions. My leadership style is listening, transparent, accessible, and supportive, while also challenging you to take your next step. Hopefully, we’ll learn a lot from each other and have plenty of fun as we break new ground at Hemnet. As a team, we get things done; we know when and where value can be added, and we’re clear on our priorities. Why did I decide to join Hemnet? I was strongly drawn to the culture and atmosphere – a wonderful combination of kindness, inclusiveness, and helpfulness, paired with high ambitions and a strong drive forward. My impression is that the people and the workplace together create the perfect foundation for you to do the best work of your career. A Note on Inclusion 💚 At Hemnet, we believe that diversity in gender, sexual orientation, ability, neurodiversity, cultural background and life experience makes us stronger. We welcome applicants of all identities and backgrounds. If you meet many but not all of the requirements, we encourage you to apply. We value curiosity, a strong sense of purpose and the motivation to learn and grow, alongside your skills and experiences. A Hybrid Way of Working 🚲 Our vibrant office in central Stockholm is the hub of our collaboration and culture, providing a lively space that fosters team spirit. We come together in the office three days a week, with two flexible remote days. To be part of our team, it’s essential to be based in or near Stockholm. Please note that we're unable to provide relocation assistance for this opportunity.

At Umain, we're not just creating software; we're crafting the future, one innovative project at a time. With our motto "Shape, Ship, Scale," we empower our team to not only envision the future but also play a pivotal role in building it. We're a dynamic team where you can shape the future, ship groundbreaking solutions, and scale your abilities in many different ways. We're on the lookout for developers ready to join us in this journey, bringing passion, creativity, and dedication along with them. The role is ideal for engineers with demonstrable skills in AI as well as for software engineers who have recently transitioned to AI and ML expertise, and offers an opportunity to develop your craft whilst working closely with clients on delivering AI solutions to real-world challenges. We are seeking an AI Engineer with experience in building robust, scaleable, AI powered solutions. The ideal candidate combines a product engineering mindset with a deep enthusiasm for advancing AI capabilities. They demonstrate a great understanding of core AI concepts, product development workflows, and embodies team spirit. AS AN AI ENGINEER AT UMAIN, YOUR ROLE WILL INVOLVE: * Assisting our clients in clarifying their questions and determining if using AI is a suitable solution for them * You understand the limitations of a model and how to address them within the product's UX * Experience architecting agentic solutions (context, memory, and tool/skill handling) and implementing them using frameworks such as Mastra, Microsoft Agent Framework, LangChain/LangGraph. * Applying stochastic test casing and trace-based reasoning to evaluate, test, and improve agent behaviour, supported by observability tooling (Langfuse, Promptfoo, etc.). * Understanding and applying core AI concepts such as redlining, document chunking for accuracy, efficient use of embeddings, and debugging AI systems * Validating, deploying, monitoring, and maintaining built models, ensuring they can be used at scale * Developing and maintaining end-to-end data pipelines and machine learning workflows, optimizing for performance and reliability * Working with diverse, cross-functional teams on projects that deliver groundbreaking AI solutions for global brands WE ALSO WELCOME EXPERIENCED SOFTWARE ENGINEERS LOOKING TO TRANSITION INTO AI: * Strong product development background with several years of software engineering experience * Active engagement in AI (agents, wrappers, context engineering) * Knows how to work efficiently in a product/engineering team WHO YOU ARE: We value candidates who demonstrate: * Great delivery skills: Proven capability to deliver AI solutions * Strong AI intuition: A deep understanding of AI concepts * Curiosity: Enthusiasm for emerging technologies, creativity in problem-solving, and an eagerness to learn in a rapidly evolving AI landscape * Full-stack product thinking: Frontend or backend experience outside the traditional AI field, with the ability to build end-to-end * You're a developer with a passion for innovation and a knack for problem-solving. * You're eager to learn, grow, and take on new challenges. * You value collaboration, diversity, and the opportunity to make a significant impact. * You believe in the power of technology to shape the future. WHAT WE OFFER: * A chance to work closely with global brands on a range of diverse and unique projects that explore and truly push the boundaries of what's possible. * A fun and fair work environment where you have the opportunity to expand your skills through unique challenges and fantastic colleagues. * A personal coach, and a setting where you can grow professionally and personally. * Being part of multidisciplinary teams, participating in agile teams, being an important player in a highly ambitious setting. WHY UMAIN? Career Framework: We believe in fairness and clarity, which is why we've established a transparent career framework to ensure equal pay and equal opportunities for all. Your growth and success are as important to us as they are to you. Together with your coach, you will build your own development plan and grow in your career. Work-Life Balance: At Umain, diversity is our strength. We understand that life doesn't pause when you walk into the office. That's why we've cultivated an environment that supports an excellent work-life balance. We welcome team members from all walks of life, recognizing the richness that different backgrounds, ages, and life stages bring to our team. We're committed to supporting each other, encouraging a healthy work-life balance that respects your needs, whether it's taking care of your family, your pets, or yourself. Innovations and Learning: Technology is always evolving, bringing new challenges and opportunities for collaboration and learning. Our developers work closely with designers, analysts, testers and more to tackle these challenges head-on, sharing knowledge and growing together. Skills Over Degrees: We're more interested in what you can do than in the diplomas you hold. Talent, drive, and creativity are what count at Umain. Here, you'll find opportunities to grow, learn, and excel in your career, regardless of your educational background. If you have the ambition and commitment to succeed, we have the environment and resources to support your journey. Background Check: Umain conducts a background check for final candidates in accordance with our internal policies. The check is carried out only with your consent and is ordered by our CISO through our approved screening partner. The scope of the check depends on the role level. This step is performed late in the recruitment process and is used solely to support a secure and fact-based hiring decision.