Fullstack Java + React Developer (Java/Spring Boot/React + AI Tooling) - Portugal Remote

ABOUT THE OPPORTUNITY

We are looking for two Full Stack Engineers — one Senior and one Mid-level — to help build, evolve and operate scalable digital products that deliver real value to customers and internal teams. You will work across the full stack, contributing throughout the software development lifecycle: from API design and distributed backend services to modern, accessible web interfaces. This role combines strong hands-on engineering across the Java and JavaScript ecosystems with the practical use of approved AI-assisted development tools as part of a modern engineering workflow. You will own features end to end, in a team where technical decisions are discussed rather than dictated.

PROJECT & CONTEXT

The client is a well-established player in the retail sector, operating large-scale, high-traffic digital platforms where performance, reliability and scale are daily engineering concerns. The ecosystem is built on distributed, containerised services with a modern React/Next.js frontend layer and a mature CI/CD and observability culture. AI tooling is an established part of how the team works — not an experiment — and engineers are expected to use it critically, validating and improving what it produces. You will join a product-oriented team with a stable roadmap and a platform used by a large customer base.

WHAT WE'RE LOOKING FOR (Required)

AI-assisted engineering

• Practical experience using AI tooling to support development activities: code generation and refactoring, test creation and automation, documentation generation, code analysis and review, and technical investigation
• Ability to review, validate and improve AI-generated output to ensure quality, security and maintainability

Backend

• Strong commercial experience developing software with Java (recent versions — Java 17 LTS or above) and Spring Boot 3.x
• Experience building and operating distributed systems, RESTful APIs and microservices
• MySQL 8 — schema design, query optimisation and performance tuning
• AWS — building, deploying and maintaining cloud-native applications

Frontend

• Strong commercial experience with JavaScript and TypeScript
• Experience building modern web applications with React 18
• Strong understanding of web performance, accessibility and responsive design

Engineering practices

• Strong understanding of software engineering best practices, testing, code quality and maintainable code
• Strong understanding of CI/CD practices and modern software delivery approaches
• Experience with containerisation technologies
• Understanding of infrastructure, monitoring and observability practices
• Strong problem-solving skills and the ability to contribute effectively in a collaborative, cross-functional team
• Fluent English, spoken and written (working language of the project)

NICE TO HAVE (Preferred)

• Next.js in production environments
• Kubernetes and container orchestration platforms
• Apache Kafka or other event-streaming technologies
• Modern observability and monitoring tooling
• Experience in large-scale digital, retail or eCommerce environments
• AWS certifications
• Portuguese language skills

Compensation: €2550 – €3350/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