Who We Are Adaptiq is a technology hub specializing in building, scaling, and supporting R&D teams for high-end, fast-growing product companies across a wide range of industries. About the Product Our client is an established technology company developing a sophisticated B2B SaaS platform that helps organizations streamline complex processes, manage digital operations, and deliver customized solutions to their customers. The product serves a substantial international customer base and has evolved into a mature, feature-rich ecosystem with a strong focus on flexibility, automation, and scalability. Its architecture supports demanding production workloads, complex data processing, and a wide range of integrations with external systems and services. The engineering team tackles exciting challenges around existing components, distributed systems, scalability, concurrency, and performance optimization, while continuously modernizing the platform and delivering new features in a fast-paced, AI-driven development environment. About the Role We are looking for a Senior Back End Engineer who combines strong backend expertise with an AI-first mindset, product thinking, and a high level of ownership. You will join a cross-functional R&D team working on the development and continuous improvement of a large-scale SaaS platform. In this role, you will take ownership of critical back end components, design and implement scalable solutions, and address complex engineering challenges related to performance, concurrency, and system reliability. This is a fast-paced environment where engineers are empowered to make decisions, manage multiple priorities, and drive projects forward independently. We are looking for an autonomous, proactive engineer who is comfortable navigating ambiguity, managing multiple priorities, and using modern development practices, including AI-assisted tools, to deliver high-quality solutions efficiently.

What You Will Do Design, develop, and maintain scalable backend services using Java and Spring Boot. Take end-to-end ownership of features, from loosely defined requirements to production-ready solutions. Design and optimize backend architecture, including concurrency, multithreading, databases, and distributed services. Leverage AI coding tools daily to accelerate development, solve complex problems, and improve engineering productivity. Manage multiple tasks and development workflows in parallel, effectively prioritizing and driving delivery. Proactively collaborate with product, architecture, and engineering teams to clarify requirements, resolve blockers, and move projects forward. Contribute beyond traditional backend boundaries when needed, including integrations, infrastructure-related challenges, and adjacent technologies. Maintain high engineering standards through automated testing, code reviews, and continuous improvement.

What We're Looking For 5+ years of professional software development experience, with strong hands-on expertise in Java. Solid experience with Spring / Spring Boot, relational or NoSQL databases, and backend system design. Strong understanding of multithreading, concurrency, and core Java concepts. Advanced, daily hands-on use of AI development tools such as Claude Code, Cursor, Codex, or similar, with practical experience integrating AI into real development workflows. Ability to critically evaluate AI-generated code, make sound technical decisions, and maintain high engineering standards. Proven end-to-end ownership, independence, and ability to turn ambiguous requirements into working solutions. Strong product mindset, proactive problem-solving, and the ability to manage multiple priorities in a fast-moving environment. Willingness to work across technical boundaries rather than limiting yourself to backend development. Strong communication skills and the ability to collaborate effectively in English.

Nice to Have Familiarity with front end technologies such as JavaScript, TypeScript, React Experience in fast-paced product development environments. Familiarity with REST APIs, event-driven architectures, and asynchronous processing Familiarity with AWS infrastructure, serverless components, or containerized environments Exposure to cloud infrastructure, CI/CD pipelines, or DevOps practices.

Why Join Us 20 days of paid vacation per calendar year, plus official public holidays in your country of residence. Full accounting and legal support in the countries where we operate. Fully remote work with a powerful workstation and access to a co-working space when needed.