Senior Backend Engineer (m/f/d) – Kotlin/Spring Boot/AWS

Join our dynamic team as a Senior Backend Engineer and play a pivotal role in developing cutting-edge applications that leverage Kotlin, Spring Boot, and AWS. You will work closely with cross-functional teams to architect and optimize backend systems that meet the demands of our growing user base.

Join us at Delivery Hero as a Senior Manager in Software Engineering focused on Logistics and Time Estimations, where your efforts will enhance the customer experience globally.As part of our Logistics Team, you will confront significant challenges aimed at making last-mile delivery not only efficient and affordable but also sustainable. Your contributions will directly improve the experiences of riders, end customers, and merchants worldwide. Each improvement you implement will assist Delivery Hero in optimizing delivery operations, facilitating our expansion into new domains such as grocery and retail.Our domain prioritizes creating a predictable, explainable, and trustworthy delivery experience throughout the order lifecycle. We achieve this by leveraging data to make accurate predictions, setting customer expectations prior to order placement, managing any deviations post-order, and providing clear and reassuring order tracking to maintain trust even when circumstances diverge from the initial plan.Your Mission:Lead the teams responsible for developing the foundational components of our customer time prediction systems.Ensure high reliability and performance of multiple low-latency, high-throughput systems that generate time predictions, focusing on enhancing domain-level service level objectives (SLOs) and service level agreements (SLAs).Collaborate with Product, Operations, and Analytics to maximize the impact of engineering on business KPIs.Coordinate with stakeholders across various teams and work alongside other domain leaders in Logistics and Regional Brands to guarantee seamless integrations.Manage and mentor engineering managers and senior individual contributors across three squads, establishing a robust delegation framework to empower decision-making at the closest context.Shape the long-term vision of the domain by translating tribe-level objectives into a coherent technical roadmap while balancing feature development with reliability, cost efficiency, and modernization initiatives.

Join our dynamic team at idealo as a Senior Software Engineer for our mobile app backend and play a pivotal role in enhancing our award-winning e-commerce applications. Our platform empowers millions of users to compare prices seamlessly and make informed purchasing decisions directly from their mobile devices. As part of a fully autonomous team dedicated to mobile app development, you'll balance the use of established technologies with innovative experiments, ensuring we continually deliver exceptional user experiences and further idealo's mission. We take full ownership of the operation, technical implementation, and strategic direction of our services, and we're seeking talented individuals to support our growth.About Your RoleEnd-to-End OwnershipDevelop and operate business and web services in the AWS Cloud.Oversee the entire lifecycle of your services (YBYO): architecture, infrastructure, development, testing, security, deployment, monitoring, on-call, and maintenance.Design and develop APIs (REST/GraphQL) for our mobile applications (Android & iOS).Ensure that our services are scalable, stable, and high-performing, even during peak loads.Technical ExcellenceMake architectural decisions for modern backend systems (e.g., microservices).Enhance our cloud infrastructure using tools like Terraform and Kubernetes.Maintain high software quality through rigorous testing, code reviews, and monitoring.Identify and address technical debt effectively.Introduce new technologies and continuously refine our development processes (e.g., CI/CD, automation, AI tools).Collaboration & ImpactWork collaboratively with mobile engineers (iOS & Android) and backend colleagues.Contribute actively to technical discussions and challenge existing solutions.Share your expertise within the team through pair programming, code reviews, or tech talks.Communicate complex technical topics clearly to non-technical stakeholders.Assume responsibility within the team, including participation in on-call rotations during critical situations.

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.

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!

As a Team Lead Java Engineer in our Remarketing department, you will spearhead architecture, solution design, development, quality assurance, deployment, monitoring, and maintenance within our service-oriented platform. This platform currently features over 300 RESTful microservices. You and your team will take ownership of a selection of applications and services.Leverage your hands-on experience and proactive attitude to tackle complex challenges effectively, providing innovative solutions and technical guidance grounded in your robust technical expertise.Take charge of the professional growth and development of your team, fostering an environment where everyone strives to improve daily.Recruit top-tier talent, exemplify leadership, and mentor your team members to push boundaries and achieve excellence.

dreessommerse seeks a Construction Logistics Manager (m/f/d) to join the team in Berlin. This role centers on managing and coordinating logistics for construction projects, ensuring that each phase runs smoothly from start to finish. Key responsibilities Oversee logistics for active construction sites, keeping all processes aligned and on track Coordinate schedules and resources, aiming for efficient and timely project execution Collaborate with project teams to help meet delivery goals Location This position is based in Berlin.

Join Our Innovative Team at 1GLOBALAt 1GLOBAL, we are redefining mobile connectivity on a global scale. As a leading technology-driven mobile communications provider, we deliver seamless connectivity solutions for both enterprises and consumers. Our advanced telecom platform, featuring our proprietary global mobile core network and in-house developed eSIM technology, empowers us to operate as a fully regulated telecommunications provider across 40 countries worldwide.We partner with some of the world’s premier banks, enterprises, and digital-first businesses, including neo-banks and global consumer goods companies. With over 70 million connections, we enable our clients to innovate and scale their operations confidently within the mobile ecosystem.As a profitable and rapidly growing business, we project revenues exceeding US$200 million in 2025, with profits surpassing US$25 million. Our strong cash flow allows us to invest continuously in our infrastructure, platform innovations, and global expansion initiatives. Our recent successes have marked a pivotal phase in our journey, with significant client acquisitions propelling us into a global mobile connectivity powerhouse.Founded in 2022 by seasoned tech entrepreneurs Hakan Koç and Pyrros Koussios, 1GLOBAL is quickly emerging as a European technology leader, committed to shaping the future of global telecommunications. As a fully regulated Mobile Virtual Network Operator (MVNO) in 12 countries and a regulated telecom operator in another 28, we are headquartered in the Netherlands with R&D hubs in Lisbon, Berlin, and São Paulo. Our dedicated team of nearly 500 experts across 15 countries is driven by a singular ambition: to enhance global mobile connectivity through innovative technology and operational excellence.About the RoleDesign and develop impactful features while contributing to the architectural framework with a focus on resilience, scalability, security, and fault tolerance.Champion high code quality and best practices to maintain robust software development.Work collaboratively in an agile team environment to ensure timely product delivery and management.

dreessommerse seeks a Logistics Planner (m/f/d) in Berlin to support construction management activities. The role centers on improving logistics for construction sites and assisting teams directly on location. Key responsibilities Refine logistics processes for both current and future construction projects Coordinate the flow of materials to maintain timely delivery and availability Collaborate with internal colleagues and external partners to ensure steady operations Location This position is based in Berlin.

About the CompanyJoin coretylynt, an innovative AI-driven trade platform that is revolutionizing industrial supply across infrastructure, energy, and construction materials. Our platform connects carefully vetted suppliers from Asia, Europe, and the GCC region with local demand, all through a single, integrated system.Leveraging our proprietary AI technology, we digitize and automate the entire lifecycle of materials trade—from procurement and pricing to inventory management, logistics, and embedded financing—effectively replacing countless manual and relationship-driven processes with real-time orchestration.Our buyers receive instant quotes, dependable availability, and predictable delivery via a unified operating system, while suppliers benefit from accurate forecasts, stringent demand management, and seamless integration into cross-border fulfillment networks. We collaborate with leading brands to efficiently execute both dropship and cross-dock fulfillment for large-scale transactions, transforming global supply chains into predictable, repeatable workflows akin to software.With the backing of top-tier investors and institutional financing partners, coretylynt has achieved significant growth, operating across six international markets and on the path to profitability. Our dynamic team of over 80 professionals based in Berlin and Asia is dedicated to building the world’s first industrial-grade AI operating system for materials—redefining the landscape of global trade in one of the world’s most essential industries.Our Supply Chain & Logistics department is at the very heart of our operations, managing real-time data flows, intricate routing logic, and integrations with a diverse ecosystem of providers. In this role, you will play a pivotal part in shaping the systems that enhance operational predictability and scalability for our clients.Tech Stack: Java 21 (Spring Boot 3), Python, PostgreSQL, Kinesis, AWS, Terraform, GitHub Actions, Node.js, TypeScript.

About the Companyandercore is an innovative AI-driven trade platform revolutionizing the industrial supply chain across infrastructure, energy, and construction materials. By linking vetted suppliers from Asia, Europe, and the GCC region with local demand, we create a seamless, integrated experience for all stakeholders.Our proprietary AI technology digitizes and automates the entire lifecycle of materials trading—from procurement and pricing to inventory management, logistics, and embedded financing—effectively replacing outdated manual processes with real-time orchestration.Buyers receive instant quotes, assured availability, and reliable delivery through our unified operating system, while suppliers benefit from enhanced forecasting, disciplined demand management, and smooth integration into global fulfillment networks. Partnering with leading brands, we facilitate both dropship and cross-dock fulfillment for large-scale transactions, transforming global supply chains into predictable, software-like workflows.With triple-digit-million GMV and operations in six international markets, we are on a rapid path to profitability. Our dynamic team of over 80 professionals in Berlin (HQ) and Asia is dedicated to developing the world’s first industrial-grade AI operating system for materials, redefining the landscape of global trade in one of the most critical industries.andercore is supported by top-tier investors and global institutional banking partners, having successfully closed a $40m Series B funding round with contributions from Atomico, Project A, and Invent Capital, alongside institutional backing from Commerzbank and KfW.Our Supply Chain & Logistics domain is central to our operations, managing real-time data flows, intricate routing logic, and integrations within a fragmented ecosystem of providers. Join us in shaping the systems that ensure predictable and scalable operations for our customers.Tech Stack: Java 21 (Spring Boot 3), Python, PostgreSQL, Kinesis, AWS, Terraform, GitHub Actions, Node.js, TypeScript.

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...

Join Atolls, the world's largest community-driven shopping platform, active in over 20 markets.We empower millions to make informed spending choices across the discovery, evaluation, and (re-)purchase phases by connecting consumers with the right brands and retailers.Our diverse team of over 1,000 individuals across 10 countries develops products that millions use daily at a global scale. Here, you'll have true ownership of your work and witness its direct impact. Are you ready to help shape the shopping experiences that people trust? Keep reading.About This Opportunity:We are on the lookout for a Senior Software Engineer (Java/SpringBoot) to enhance our Shopping team based in Berlin. In this pivotal role at Atolls, you will play a critical part in enabling our consumers to maximize their value for money by delivering an outstanding shopping rewards experience online and in-store. You'll be instrumental in crafting exceptional user experiences, empowering consumers to make informed and confident shopping decisions. Your contributions will directly influence how millions of users engage with our platforms, guiding them towards making smart, fair, and rewarding choices.Our Perks:At Atolls, we are committed to fostering your professional and personal development. Here’s what we offer:A culture that champions personal and professional growth, coupled with internal mobility opportunities.A supportive and inclusive team that values diverse perspectives and innovative ideas.32 days of paid vacation plus your birthday off for optimal work-life balance.A flexible hybrid working model to accommodate your lifestyle.Access to a dedicated learning budget and internal training.Mental health coaching to support your well-being.Regular global and local events to celebrate achievements and foster connections.Opportunity for a sabbatical after three years with the company.

Join our dynamic team as the Director of Engineering for Pricing and Data in Logistics (all genders) at Delivery Hero. In this pivotal role, you will spearhead efforts to enhance our Pricing and Data domains, ensuring we consistently deliver exceptional experiences to our customers.As a member of our Logistics Team, you will confront significant challenges aimed at optimizing last-mile delivery, making it efficient, affordable, and sustainable. Your contributions will not only enhance the experiences of riders, customers, and merchants globally but will also support Delivery Hero's expansion into new sectors like grocery and retail.Leading a diverse team of over 40 engineers, data scientists, and managers, you will drive strategies that optimize pricing for long-term profitability across all markets. Collaborating closely with product and business teams, you will influence our pricing strategy and report directly to the Vice President of the Logistics Customer Product Line.Your mission includes:Empowering a diverse, cross-functional tech team and its leaders to achieve impactful results.Developing and implementing innovative pricing mechanisms and management features to foster profitable growth.Collaborating with regional managers and brand leadership to address local needs through scalable centralized product offerings.Enhancing our data and machine learning platforms to make Logistics an exceptional environment for data utilization and model deployment.

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.

Join our dynamic team at flink3 as a Junior Workforce Support Specialist. In this role, you will be pivotal in enhancing our operational efficiency and supporting our workforce with essential resources and tools. Your contributions will directly impact our ability to deliver exceptional service to our clients and partners.

dreessommerse seeks a Construction Manager (m/f/d) in Berlin to oversee construction projects with a focus on logistics. This role manages the entire project lifecycle, starting with early planning and continuing through to final delivery. A key part of the job is ensuring that logistics are well coordinated at every stage. What you will do Supervise all construction activities from initiation to completion Coordinate resources and manage project schedules to meet deadlines Monitor compliance with safety regulations and established standards Direct logistics operations to support smooth and efficient project progress Location This position is based in Berlin.

Join Delivery Hero as a Software Engineer II specializing in Golang for our Logistics team. In this role, you will contribute to the development of innovative solutions that streamline our global service technology.We are looking for passionate engineers who are eager to tackle complex problems and create scalable applications that enhance our delivery services.

idealo’s White Labels team builds and maintains dynamic websites that present idealo’s data in new and engaging ways. Operating in six European countries, the group supports one of Western Europe’s leading price comparison platforms. This role combines hands-on coding with opportunities to shape the user experience and connect with major platforms such as Google and Bing. What You Will Do Develop, operate, and improve scalable, highly available web applications running on AWS. Help plan, structure, and refine new features from concept through delivery. Contribute to product development as part of a cross-functional team, taking on responsibilities beyond coding alone. Work across the stack, focusing on backend development but also working with frontend technologies including HTML and CSS3. Location 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.