Senior Fullstack Java Developer

About Block LabsBlock Labs is a premier technology studio operating at the bleeding edge of Web3, Artificial Intelligence, and iGaming.We don't just ship features; we engineer high-scale, production-grade platforms that power the next generation of digital products.We are a collective of senior engineers, product strategists, and builders who refuse to compromise on architecture.Whether we are designing autonomous multi-agent AI systems, building decentralized financial infrastructure, or architecting high-frequency iGaming platforms, our standard is excellence.We move fast, but we build for the long term.If you are looking to work alongside a team that values deep technical expertise, thoughtful system design, and product ownership, Block Labs is where you belong.About The RoleYou will join a multidisciplinary engineering team working on real-time multiplayer and single-player gaming platforms.This role is ideal for a developer with a strong Java background who can work confidently across backend services, frontend integrations, and supporting tools.A genuine engineer who can take ownership of features end to end.This is not a narrow backend role and not a ticket factory.We are looking for a Senior Java Engineer who can reason about systems end to end and take responsibility for features from design to production.You will primarily work in Java, but you are expected to step outside strict role boundaries when necessary: defining protocols, debugging production issues across services and clients, and making pragmatic engineering decisions.Key ResponsibilitiesDesign and implement backend services in Java 17+ using Spring Boot and MavenOwn critical microservices across authentication, gameplay, chat, and real-time communicationDesign and maintain REST and WebSocket APIs with a strong focus on correctness, latency, and resilienceWork closely with client engineers to define protocols, state synchronisation, and integration contractsBuild and maintain integrations with third-party platforms and cashier systemsContribute to data modelling, schema design, and query optimisationDebug complex production issues that cut across services, networks, and client behaviourParticipate actively in code reviews, architectural discussions, and technical decision makingEnsure scalability, consistency, and reliability across distributed systemsAbout YouYou are genuinely strong in Java (17+) and have built real systems with Spring BootYou have experience owning services in production, not just writing codeYou understand distributed systems, state management, and failure modesYou have worked with transactional systems such as payments, wallets, or financial flowsYou are comfortable designing APIs and communication protocolsYou can read and reason about frontend or client-side code, even if it is not your main focusYou value clarity, simplicity, and correctness over clever abstractionsYou take ownership and do not wait to be told what to doExperience with real-time systems or multiplayer platforms would be an advantageCultureMature, mission-driven, and low-ego.We value clarity over noise, outcomes over theatrics, and pace without chaos.If you're one of the smartest minds in your craft and want to build with other experts, you'll feel at home here.Seniority level: Mid-Senior levelEmployment type: Full-timeJob function: Engineering and Information TechnologyIndustries: Technology, Information and InternetReferrals increase your chances of interviewing at Block Labs by 2x.Get notified about new Senior Java Software Engineer jobs in Montenegro, Rio Grande do Sul, Brazil.#J-*****-Ljbffr