We are looking for talented Senior Java Engineer to join our team in Poland. Our California-based customer is an American global e-commerce leader, one of the most popular and successful websites on the Internet. It provides platform services by connecting millions of sellers and buyers in more than 190 markets around the world. The Senior Java Engineer will be a part of the AI Core team to bring new experiences for sellers and buyers leveraging Machine Learning models and other Artificial Intelligence tools to maximize the fun and accuracy of shopping experience. Main Responsibilities:Design, build, and maintain efficient, reusable, and reliable codeSuggest technical and functional improvements to add value to the productConduct design and code reviews to deliver high quality productMinimum Requirements:At least 5 years of proficiency in JAVA or Kotlin technologiesDeep experience with the Spring FrameworkExperience with NoSQL databases (one year at least)Knowledge of different communication protocols such as REST, gRPC, and GraphQLVery good spoken and written knowledge of English language (C1)BSc or MSc in Computer Science, Engineering or relevant fieldPreferred RequirementsAn experience with Apache Kafka and its architecture for real-time data streamingExperience with reactive programming (Project Reactor)Experience with Docker for containerization of applicationsFamiliarity with Kubernetes for container orchestration and managementExperience with large-scale distributed systems.Professional growth:Strong engineering cultureChallenging projects and mature teamsPersonalized on-demand cross-company mentoring support enabling you to learn new things fasterPlenty of opportunities to share knowledge and get more experience such as opportunity to mentor others, speak at events, and contribute to pre-salesDirect communication with the customerAn individual education budgetA friendly, supportive and dynamic work environmentCare, comfort and funA relocation packageFlexible working hoursHealthcare & sport benefitsCorporate events, outstanding parties and team buildingsWe offer:Flexible working format - remote, office-based or flexibleA competitive salary Personalized career growthProfessional development tools (mentorship program, tech talks and trainings, centers of excellence, and more)Active tech communities with regular knowledge sharingEducation reimbursementMemorable anniversary presentsCorporate events and team buildings