Java Developer for a Fintect Project (b2b, full-time, Poland-based)

S*** S*** IncS*** S*** Science Inc is a U.S.-based fintech company operating in the investment and financial services space. Our distributed teams work across Poland, the United States, and Ireland, collaborating on technology-driven solutions related to stocks and investments.Security, compliance, and the responsible handling of sensitive financial data are central to how we operate as we build scalable products in a regulated environment.ProjectThe engineer will initially get familiar with the product, domain, and existing codebase by working on current issues and fixes. After onboarding, the role will gradually expand into the development of new change requests and product enhancements.The project is focused on backend development within a complex fintech environment involving distributed systems, microservices, event-driven architecture, cloud technologies, and data-intensive applications.RequirementsWe are looking for an experienced backend engineer with strong hands-on experience in:Core Java and SpringServer-side developmentSQLMicroservicesREST APIsKafka and event-driven architecturesPythonKubernetesGitHubRedis and cachingAzureSnowflakePostgreSQLCloud-native developmentCI/CDDistributed systemsConcurrencyMulti-tenancyData governanceExperience with modern LLM and agentic technologies is highly valuable, including:Prompt engineeringModel Context Protocol (MCP)Retrieval-Augmented Generation (RAG)LLM/agentic developmentEngagement DetailsInitial contract duration: 1 year, with the possibility of extension based on performance and skill setHourly remuneration: $32.5 USD/hour for a Middle engineer - 35 USD/hour for a Senior EngineerEngagement: Full-timeLocation / time zone: PolandWorking language: EnglishWorking hours: Standard Polish working hours, with at least 4 hours of overlap with U.S. Eastern TimeRecruitment ProcessThe recruitment process follows our standard interview stages, including technical and client-side evaluation.Important - Please Read Before ApplyingThe client is building a product in the banking, investment, and brokerage systems domain. Due to strict investor, security, and compliance requirements, every candidate must successfully complete a background check.For this reason, candidates must:be currently based in Poland;have been a taxpayer in Poland for at least 2 years;be able to provide the required documentation for the background-check process.We are looking for someone who can quickly understand an existing system, resolve complex backend issues, and gradually take ownership of new development in a security-sensitive fintech environment.