Senior AI Engineer with Java - Portugal Full Remote

Senior AI Engineer (Java/LangChain) - Full Remote Portugal ABOUT THE OPPORTUNITY We are partnering with an innovative, global software engineering company focused on building high-impact technology that improves lives. We are seeking a highly skilled Senior AI Engineer to help shape the next generation of intelligent enterprise applications. This is an exciting opportunity to work at the intersection of robust backend architecture and cutting-edge artificial intelligence. You will take ownership of advanced LLM integrations and autonomous agent workflows, working within a highly collaborative, human-centric culture. In this role, you will partner closely with App Engineers, Product Managers, and cross-functional development teams to define innovative AI use cases and deliver seamless end-to-end user experiences for mobile applications. PROJECT & CONTEXT The project focuses on the architecture, development, and maintenance of scalable, high-performance microservices and agentic AI systems. You will lead the design and implementation of autonomous AI agents capable of multi-step reasoning, dynamic tool utilization, and long-term memory management. Your technical landscape will involve integrating commercial large language models, specifically Azure Co-pilot, into enterprise applications via robust RESTful APIs. You will also implement critical AI system reliability measures—including guardrails, rate limiting, fallback mechanisms, and observability tracing—to guarantee enterprise-grade security and performance. A significant part of the engineering process will require you to craft, test, and version-control complex prompts using skills and agents markdown files to ensure deterministic, safe, and accurate model outputs. WHAT WE'RE LOOKING FOR (Required) Bachelor's degree in Computer Science, Engineering, or a related technical field Minimum of 8 years of relevant professional engineering experience Proven track record as a Java Developer, with deep expertise in designing scalable backend microservices Hands-on programming experience using Java 17, Java 21+, and the Spring Boot framework Strong knowledge of agentic AI frameworks such as LangChain, LangChain4j, or Spring AI Practical experience with prompt engineering, prompt optimization, and LLM fine-tuning for production Experience building, maintaining, and integrating robust RESTful APIs Exceptional technical writing skills for documenting architectures, APIs, and writing comprehensive developer guides Excellent communication skills in English (both written and spoken) for daily team collaboration NICE TO HAVE (Preferred) Prior experience integrating enterprise AI features into Mobile Application ecosystems Extensive hands-on experience specifically with Azure Co-pilot and the broader Azure cloud ecosystem Proven experience implementing specialized observability and tracing for LLM workflows Experience working in highly cross-functional agile teams alongside frontend developers, data engineers, and product managers Compensation: €2,850 – €3,800/month net, depending on experience and seniority level. Why HumanIT people stay (4.4 Glassdoor, 89% recommend) - 15th month salary - Health insurance covering your family - Birthday off - Mobility program for digital nomads - Real work-life balance Full benefits https://www.humanit.pt/careers/#perks What it's really like https://www.humanit.pt/careers/#work-at