Senior Kotlin/Java Software Engineer - Banking Platform (m/f/x)

Doctolib is hiring a Software Engineer with solid experience in Java and Kotlin. This position is based in Berlin and centers on building digital products that support both patients and healthcare professionals across Europe. Role overview This role involves working on software that aims to improve healthcare access and efficiency. The team values collaboration and a shared commitment to making a difference in the medical field. What you will do Collaborate with team members to design and implement new product features Develop and maintain applications using Java and Kotlin Help create solutions that make healthcare services easier to access and manage Location This role is based in Berlin, Germany.

Join our Clickout-to-Revenue Team, where you'll be integral to our core business model: merchants pay for qualified redirects ("Clickouts") to their shops. Your role will ensure that this monetization operates smoothly, efficiently, and transparently, significantly contributing to idealos' growth.Your ResponsibilitiesEnd-to-End Responsibility You will develop and manage business and web applications in the AWS Cloud. Together with your team, you will oversee the entire value chain (YBYO): architecture, infrastructure, development, testing, security, deployment, monitoring, on-call duties, and maintenance. Product Focus: Monetization Processes and Services You will develop services for the representation and billing of our business models. Key components include the ERP system Odoo, internal data management tools, and interfaces to Salesforce and SAP. Innovative business models require innovative solutions; hence, you will closely collaborate with stakeholders such as our accounting, sales teams, account management, and other cross-functional engineering teams. Technical Excellence You will actively contribute ideas for process improvements, emphasize high code quality, and engage in continuous personal development – we support you with various training opportunities.

Join idealo’s Clickout-to-Revenue team in Berlin, where the focus is on building and maintaining systems that help retailers monetize qualified referrals. The team’s work has a direct impact on idealo’s growth by ensuring monetization processes remain reliable and efficient. Both full-time and part-time arrangements are possible for this Senior Software Engineer position. What you will do Design, develop, and operate business and web applications on AWS Cloud. Take responsibility for the full lifecycle: architecture, infrastructure, development, testing, security, deployment, monitoring, and maintenance. Build and maintain services that handle processing and billing, integrating with key systems such as Odoo ERP and connecting to Salesforce and SAP. Work closely with colleagues from accounting, sales, account management, and other engineering teams to deliver solutions that meet changing business needs. Identify and implement process improvements, maintain high code quality, and pursue ongoing professional growth with support from idealo. Tech stack Kotlin Java AWS Odoo ERP Salesforce and SAP interfaces Location This role is based in Berlin, Germany.

About Us Join our dynamic international team at Doctolib, based in Berlin, where we are devoted to enhancing the performance, features, and design of our essential healthcare product, the Scheduling System. Over the past decade, Doctolib has experienced remarkable growth by prioritizing pragmatic solutions and avoiding unnecessary optimizations. To sustain our momentum, we are focusing on performance as a key priority and are continuously evolving the architecture of our core features to accommodate future demands. We are currently re-engineering our Appointments Management Service from the ground up, utilizing modern event-driven, distributed technologies in line with our updated technology strategy. This pivotal service will revolutionize the way Care Teams manage appointments, ensuring patients receive quicker access to care.

About the Role scalablegmbh is looking for a Senior Kotlin / Java Software Engineer focused on Application Framework development in Berlin. This position centers on designing and building scalable applications that support core business functions. The work directly influences our technology choices and strengthens the software we deliver.

At Flix, we foster a technology-driven culture where creativity meets significant real-world applications. We offer competitive compensation, ample opportunities for professional advancement, and a collaborative environment that encourages ownership and innovation.We are on the lookout for a Software Engineer (Kotlin, Java) with robust Kotlin (or Java with a willingness to learn Kotlin) expertise to become a key member of our Capacity Management team in the Demand Division. The Capacity Management team is responsible for developing and maintaining systems that allocate, price, and manage seat availability across Flix. Our team handles high-throughput, real-time data pipelines and event-driven microservices to ensure smooth operations, even in unpredictable situations.As a Software Engineer at Flix, you will have the opportunity to influence systems that directly affect how millions of passengers book their seats and optimize Flix's capacity across our global network in real-time.Our tech stackLanguages & Frameworks: Kotlin, Spring Boot, Akka/PekkoData & Messaging: PostgreSQL, Kafka

About Our Team At SumUp, we provide a cutting-edge Point-of-Sale (POS) solution that empowers businesses such as cafes, shops, bars, and hair salons to operate seamlessly and grow. Our platform boasts a vast array of features, including product catalogs, inventory management, business analytics, compliance support, and loyalty tools. Our POS solution integrates flawlessly into the SumUp SuperApp, which is compatible with our proprietary register hardware as well as mobile devices like tablets and smartphones. As a Senior Android Developer, you will work alongside an innovative, cross-functional team consisting of Product Managers, Product Designers, Engineering Managers, and fellow developers. About the Role We are transitioning towards a Kotlin Multiplatform (KMP) strategy, facilitating shared development between Android and iOS. In this role, you will gain experience with this technology, helping to shape the future of our mobile applications. If you are a developer who prioritizes user-centric design, precision, and effective collaboration, you will thrive here. You bring structure to communication and flourish within a cross-functional environment. This position is based in Berlin, where face-to-face interactions fuel innovation and teamwork. Your Responsibilities Develop new features for the item catalog within the SumUp SuperApp Improve application architecture and actively contribute to our Kotlin Multiplatform strategy Enhance and maintain our unified Android app, utilized in over 60 countries, ensuring high-quality and scalable solutions Drive product evolution by identifying improvement opportunities and participating in daily decision-making Create comprehensive documentation and implement thorough testing for features prior to release Work closely with Designers, Product Managers, and Android engineers to ensure a cohesive UX experience across platforms Mentor and coach junior engineers You Will Excel in This Role If: You possess 8+ years of experience in mobile engineering, particularly with Android and Kotlin. You have 2+ years of experience with Jetpack Compose. You have a strong grasp of software design patterns (e.g., MVVM, MVI) and expertise in creating modular, scalable app architectures. You are knowledgeable about reactive programming (Flow, Coroutines, and Concurrency).

Join us at Delivery Hero as an Engineering Manager specializing in Java/Kotlin for our Logistics Workforce Tribe. We are dedicated to delivering exceptional experiences and are looking for a leader to help us achieve this goal.As part of our Logistics Team, you will address significant challenges to enhance last-mile delivery, making it more efficient, affordable, and sustainable. Your contributions will directly enhance the experiences of riders, end customers, and merchants worldwide. Each improvement you implement will assist Delivery Hero in optimizing our delivery operations, facilitating our expansion into new sectors such as grocery and retail.The Workforce Tribe Team:Riders serve as the backbone of our last-mile delivery, enabling the fulfillment of millions of orders daily.Our Workforce Tribe is responsible for managing gross and net earnings, a wallet for riders to withdraw their earnings, staffing and work scheduling, performance management, loyalty programs, personalized campaigns and goals, recruitment of new riders, and document management for our million-strong rider community.The rider experience with Delivery Hero is our core metric, and you will be at the helm of one of the squads that directly influences this metric.Your Role:Collaborate with your product counterpart to provide technical guidance to your team, facilitating the design of feasible and iterative solutions that align with our business needs.Take ownership of the technical metrics and KPIs for your team, ensuring complete visibility, monitoring, and alerting.Enhance and support the incident resolution process and the team's on-call practices.Mentor junior team members, providing both technical and non-technical guidance.Manage relationships with both technical and non-technical stakeholders, effectively navigating and resolving challenges.

idealo is looking for a Senior Backend Software Engineer (m|w|d) to join the team in Berlin. This role focuses on building and operating the backend for our mobile app, which helps millions of users compare prices and shop smarter. The team takes full ownership of technical implementation, operations, and strategic direction for our services, with a strong commitment to delivering a seamless experience for mobile shoppers. Role overview This position centers on end-to-end responsibility for business and web services in the AWS Cloud. The team manages the full lifecycle of these services, from architecture and infrastructure to development, testing, deployment, monitoring, and on-call support. The goal is to ensure stability, scalability, and high performance, especially during periods of heavy traffic. What you will do Develop and operate backend services in AWS Cloud for the mobile app Design and implement APIs (REST/GraphQL) for Android and iOS applications Make architectural decisions for backend systems, including microservices Enhance cloud infrastructure using tools such as Terraform and Kubernetes Maintain high code quality through testing, code reviews, and monitoring Identify and address technical debt Introduce new technologies and improve development workflows (CI/CD, automation, AI tools) Collaboration and impact Work closely with mobile engineers and backend colleagues Contribute to technical discussions and challenge existing solutions Share knowledge through pair programming, code reviews, and tech talks Communicate complex technical topics to non-technical stakeholders Participate in on-call rotations and take responsibility during critical incidents

At JetBrains, we are passionate about code. Since our inception in 2000, we have dedicated ourselves to creating the most powerful and effective developer tools available. By automating routine checks and corrections, our tools enhance productivity, enabling developers to innovate and create freely. Kotlin, a modern programming language developed by JetBrains, targets Java, Android, JavaScript, and native platforms. Since its introduction in 2016, Kotlin has rapidly gained traction, becoming the official language for Android development and receiving support from numerous frameworks, engines, and tools. With Kotlin Multiplatform and Compose Multiplatform, our mission is to empower Android developers to create exceptional multiplatform applications. The Kotlin Multiplatform Tooling team is at the forefront of this initiative, developing tools that simplify the process. We are actively working on Kotlin Multiplatform plugins for IntelliJ IDEA and Android Studio, alongside enhancing IntelliJ IDEA's Android support, KDoctor, and the Kotlin Multiplatform wizard. We are looking for a passionate Android developer who can share their insights and experience with our team while contributing to the development of tools that they have always envisioned. Our international and friendly team welcomes applicants who share our enthusiasm for coding.

flix is hiring a Full-stack Engineer to join the Payments Team in Berlin. This team develops and maintains the systems that process payments, focusing on both a smooth user experience and the company’s business needs. Java and Kotlin are key technologies in this role. What you will do Collaborate with colleagues across disciplines to design, build, and launch new payment features Support and enhance the systems that process payments for flix customers Share ideas and technical knowledge to help shape the direction of the payment platform Requirements Strong experience with Java and Kotlin Interest in building payment solutions Ability to work onsite in Berlin Location This role is based in Berlin.

Join our innovative team at redcare-pharmacy as a Senior Java Engineer. In this pivotal role, you will leverage your expertise in Java programming to develop robust, scalable applications that enhance our digital pharmacy solutions. Collaborate with cross-functional teams to drive the design and implementation of high-quality software solutions.We are looking for a proactive and detail-oriented engineer who thrives in a dynamic environment and is passionate about problem-solving. If you are ready to make a significant impact in the healthcare technology space, we want to hear from you!

Atolls is the world’s largest community-driven shopping platform, active in over 20 markets.We empower millions to make informed spending choices across discovery, evaluation, and (re-)purchase by connecting individuals with the ideal brands and retailers.Our team of 1,000+ members across 10 countries develops products utilized daily on a global scale, providing you with genuine ownership and the chance to witness your impact. Are you ready to help shape the destinations people trust for confident shopping? We invite you to learn more.About This Role:We are on the lookout for a Senior Java Backend Engineer to become an integral part of our expanding engineering team in Berlin. In this pivotal role, you will be responsible for designing, developing, and scaling high-performance backend systems utilizing contemporary Java technologies and cloud-native architectures. This position is perfect for individuals who thrive on tackling complex systems, prioritize code quality, and possess a robust architectural mindset.Our Benefits:At Atolls, we are committed to fostering both your professional and personal development. Here’s what you can look forward to:A culture that champions personal and professional growth, alongside opportunities for internal mobility.A supportive and open-minded team that welcomes diverse perspectives and innovative concepts.32 days of paid vacation plus an additional day off for your birthday, ensuring you have ample time to recharge.A flexible hybrid working model to help you find the right balance between work and life.Access to a learning budget and internal training to enhance your skills in your role.Mental health coaching to promote your well-being.Regular global and local gatherings to celebrate achievements and strengthen connections.The chance to take a sabbatical after three years with the company.A cloud-based company setup, allowing flexibility and collaboration regardless of your location.*These are global benefits applicable to all employees, with additional local perks based on your location.Responsibilities:As a Senior Java Backend Engineer, you will...

Your ImpactJoin our dynamic DIAL team within the Phone Assistant domain as a Senior Software Engineer. Your mission is to transform patient access to care and optimize daily practice management for healthcare providers through our innovative Phone Assistant solution.You'll collaborate within a feature team to develop cutting-edge AI-driven voice services that enhance phone interactions for millions of users in Germany, France, and Italy.At Doctolib, being part of our tech team means you are building impactful products and features aimed at improving the everyday experiences of care teams and patients alike.

At Enpal, our vision is to empower every household with sustainable energy solutions. We strive to have a solar system on every roof, a storage unit in every home, and an electric vehicle in every garage. Our comprehensive approach to decentralized energy encompasses solar systems, battery storage, wall boxes, smart meters, and heat pumps. Central to this mission is our innovative AI-powered platform, Enpal.One+, which seamlessly connects thousands of systems while optimizing electricity procurement and feed-in on the energy market.Are you ready to create solutions that do more than just promise change? Join us at Enpal, where your contributions will deliver clean, renewable electricity and significantly enhance the quality of life for countless households.Your RoleAs a Senior Software Engineer - C# (f/m/x), you will tackle intricate challenges in delivering effective renewable energy solutions. Your responsibilities will range from digitalizing the planning processes for solar panel installations through engaging frontend applications to developing APIs that support real-time energy data management and scaling cloud infrastructure in Azure.We promote an agile environment that fosters rapid personal and professional growth. Our commitment to making sustainable solar energy accessible to all can only be achieved by uniting our customer-centric approach with collaborative efforts between software development, product management, and innovative, experiment-driven business development.Join us to enhance your skills, participate in the energy revolution, and work together towards the sustainable change we aspire to see in the world!Software Development: We prioritize delivering incremental value with each iteration and celebrate improvements that enhance user experiences and contribute to our climate goals.Developer Satisfaction: We aim to enhance stability and automate processes, minimizing the need for late-night deployments and repetitive manual regression tests.Continuous Learning: Whether you're an expert in Kafka or just starting with Azure Bicep, we welcome your knowledge and are committed to supporting your growth through continuous learning opportunities.Architectural Design: You will have the opportunity to work on architecture and technical design, ensuring our solutions are robust and scalable.

At Enpal, we're on a mission to revolutionize how energy is consumed. Our vision is to provide solar systems on every rooftop, battery storage in every home, and electric vehicles in every garage. Our comprehensive solutions encompass everything from solar installations to smart meters and heat pumps, all powered by our advanced AI platform, Enpal.One+. This innovative platform seamlessly connects a multitude of systems, optimizing energy procurement and feed-in across the market.Are you passionate about creating impactful solutions that enhance the quality of life for thousands of households? Your contributions at Enpal will not only help deliver clean energy but also foster a significant shift in energy usage for the future.Your RoleAs a Senior Software Engineer - Node.js (f/m/x), you will tackle intricate challenges in the realm of renewable energy solutions. Your responsibilities will range from digitizing solar panel installation planning with engaging frontend applications to developing APIs that provide real-time energy data. Additionally, you will be instrumental in scaling and managing our cloud infrastructure on Azure.We pride ourselves on our agility and commitment to professional development. Our vision of making sustainable solar energy accessible to everyone thrives on a customer-centric approach, fostering collaboration between software development, product management, and innovative business strategies.Join us in enhancing your professional journey, participating in the energy transformation, and taking shared responsibility for the sustainable future we aspire to create! We eagerly await your application.At Enpal, you will:Build Software: We prioritize delivering incremental value in every iteration, celebrating improvements that enhance user experience and help achieve our climate objectives.Enhance Developer Happiness: We aim to automate processes, reducing manual testing and deployment times, thereby improving the overall stability of our solutions.Grow & Learn: Whether you're an expert in Kafka or new to Azure Bicep, we are committed to facilitating your growth through shared knowledge and resources.Engage in Architecture & Design: Collaborate with cross-functional teams to design scalable and robust software architectures.

JetBrains has developed tools for software teams since 2000. By automating routine checks and corrections, JetBrains products help developers focus on building and shipping software. The goal: make development more productive and creative. Role overview This Backend Customer Success Engineer role centers on supporting engineering teams as they adopt Kotlin for backend development. The position focuses on helping organizations successfully bring Kotlin into production environments. What you will do Guide organizations through the process of moving from Java to Kotlin, assisting with migration, integration, and scaling. Troubleshoot technical challenges that arise during the transition and support teams as they progress from initial experimentation to stable production use. Work with potential users to clarify how Kotlin adoption works and help design migration plans that fit their specific needs. Locations Amsterdam, Netherlands Berlin, Germany Munich, Germany Prague, Czech Republic Remote, Germany

KAYAK, part of Booking Holdings (NASDAQ: BKNG), runs a large-scale travel search platform used by travelers worldwide to find flights, hotels, rental cars, and vacation packages. The company also offers KAYAK for Business, which provides travel management solutions to organizations. Its network includes well-known brands like momondo, Cheapflights, and HotelsCombined. KAYAK aims to make exploring the world easier by building the best travel search engine and values innovation and real impact from its employees. Role overview As a Senior Java Software Engineer based in the Berlin office, you will play a key role in developing and refining the features behind KAYAK’s search and booking systems. The team collaborates with over 200 travel partners, giving users access to more than 500,000 hotels and 550 airlines. Your work will help ensure smooth, reliable experiences for millions of users each day. This position requires onsite presence in Berlin at least three days per week. What you will do Enhance search and booking algorithms to meet the needs of major corporate clients worldwide. Develop and maintain high-performance integrations with third-party APIs, including those for airlines, hotels, and rental car providers. Take ownership of your designs from concept through deployment, with a focus on code quality and system performance. Join code reviews and architectural discussions to keep the K4B project modular and reusable as KAYAK continues to grow. Requirements Bachelor’s degree in Computer Science or a related field. At least 4 years of professional experience working with Java. Strong knowledge of the Spring ecosystem (Spring/Spring Boot) and hands-on experience with both relational (SQL) and NoSQL databases such as PostgreSQL, MySQL, or Redis. Clear and effective communication skills in English. Ability to independently design and deliver engineering projects.

About KAYAKKAYAK, a member of Booking Holdings (NASDAQ: BKNG), stands as a premier travel search engine. With billions of queries on our platforms, we assist travelers in discovering their ideal flights, accommodations, rental cars, and vacation packages. We are also revolutionizing business travel with our innovative corporate travel solution, KAYAK for Business.As part of KAYAK, you will join a travel company that oversees a diverse array of global metasearch brands, including momondo, Cheapflights, and HotelsCombined. From our startup journey to becoming an industry trailblazer, innovation drives us, and every team member has the chance to leave a lasting impact. Our commitment is to develop the most efficient travel search engine, simplifying the process for everyone to explore the world.Position OverviewWe are in search of a proficient mid-level Java backend developer dedicated to implementing new features and maintaining KAYAK’s cutting-edge search and booking technology. Collaborating with over 200 travel partners and connecting to more than 500,000 hotels and 550 airlines, you will play a pivotal role in a dynamic team that ensures seamless operations, aiding millions in finding optimal accommodations and travel routes every day!This is a Fixed Term contract until September 30, 2027.This role requires working from our Berlin office a minimum of three days per week.Key ResponsibilitiesEnhance search and booking algorithms to meet the needs of our largest global corporate clients.Develop and sustain high-performance integrations with third-party APIs (airlines, hotels, and rental car providers).Take full ownership of your designs, from concept to deployment, while upholding exceptional standards for code quality and performance.Engage in code reviews and architectural direction to ensure the K4B project remains modular and reusable as KAYAK expands its enterprise reach.QualificationsBachelor’s degree or higher in Computer Science or a related field.5+ years of experience in Java programming.Hands-on experience with the Spring ecosystem (Spring/Spring Boot) and familiarity with relational (SQL) and NoSQL databases (e.g., PostgreSQL, MySQL, Redis).Excellent English communication skills.Ability to design and implement engineering initiatives with a focus on performance and usability.