Junior Java Backend Developer

📍 Lisbon | Hybrid, 3 days/week on-site

🎯 Experience: Around 2 years

🚀 About the Role

We are looking for a Junior Java Backend Developer to join a collaborative engineering team working on the evolution of digital products such as Checkout, MyAccount, and ODR Processing .

You will develop and maintain Java microservices, build and integrate APIs, contribute to automated testing and CI/CD quality gates, and gain exposure to modern Identity & Access Management technologies.

This is an excellent opportunity for an early-career developer who wants to strengthen their backend engineering skills while learning from senior engineers and participating in a structured technical upskilling programme.

🎯 Your Mission

As a Junior Java Backend Developer, you will:

• Develop and maintain Java-based microservices.
• Build and integrate RESTful and GraphQL APIs.
• Write unit and integration tests.
• Contribute to code quality and security practices.
• Support IAM integrations using modern authentication technologies.
• Participate actively in Agile development.
• Continuously expand your technical skills through mentoring and structured training.

💼 Key Responsibilities Java & Microservices Development

• Develop and maintain backend microservices using Java .
• Implement new functionalities for Checkout, MyAccount, and ODR Processing solutions.
• Work alongside senior engineers to understand technical requirements and solution designs.
• Write clean, maintainable, and testable code.
• Follow established software engineering and coding standards.
• Troubleshoot application issues and contribute to technical improvements.

API Development

• Design and implement RESTful APIs according to established standards.
• Contribute to GraphQL API development and integration.
• Follow OpenAPI documentation standards.
• Implement reliable integrations between backend applications and services.
• Support API testing and troubleshooting.

Testing & Code Quality

• Develop and maintain:
• Unit Tests
• Integration Tests
• Contribute to automated quality gates.
• Work with tools such as:
• SonarQube
• Snyk
• Identify code quality and security issues.
• Support the continuous improvement of test coverage and application reliability.

Identity & Access Management

• Support the integration of authentication and authorization flows.
• Gain hands-on experience with:
• Keycloak
• Okta
• OpenID Connect (OIDC)
• Work with senior engineers to implement secure authentication mechanisms.
• Follow established security guidelines and IAM standards.

Git & Development Workflow

• Work with GitLab-based development workflows .
• Create and contribute to merge requests.
• Follow established pull request and code review processes.
• Apply feedback from senior engineers and technical reviewers.
• Ensure developments meet defined quality and security standards before integration.

Agile Collaboration

• Work within an Agile engineering team.
• Participate actively in:
• Sprint Planning
• Daily Stand-ups
• Sprint Reviews
• Retrospectives
• Collaborate with Developers, QA Engineers, Product stakeholders, and other technical teams.
• Communicate progress, challenges, and dependencies clearly.

Learning & Upskilling

• Participate actively in the structured technical upskilling programme.
• Learn from experienced engineers and subject matter experts.
• Develop deeper knowledge of microservices, APIs, security, testing, and modern backend engineering.
• Apply newly acquired knowledge directly to project activities.
• Build greater technical autonomy over time.

✅ What We're Looking For

Key Requirements

• Approximately 2 years of professional software development experience .
• Professional experience with Java development .
• Good understanding of backend development principles.
• Knowledge of microservices concepts.
• Familiarity with REST APIs.
• Understanding of automated testing principles.
• Experience or familiarity with Git-based development workflows.
• Strong willingness to learn and develop technically.
• Ability to collaborate effectively within a team.
• Portuguese C1 .
• English C1 .

🛠 Technical Stack

Backend

• Java
• Microservices
• Backend Development

APIs

• REST
• GraphQL
• OpenAPI

Identity & Security

• Keycloak
• Okta
• OpenID Connect
• Authentication & Authorization

Quality & Security

• Unit Testing
• Integration Testing
• SonarQube
• Snyk
• Code Quality
• Security Guidelines

Development & Delivery

• GitLab
• Merge Requests
• Code Reviews
• CI/CD
• Agile

🤝 Soft Skills

• Strong learning mindset and curiosity.
• Good analytical and problem-solving capabilities.
• Team-oriented and collaborative attitude.
• Openness to technical feedback and mentoring.
• Attention to code quality and security.
• Proactive approach to personal and technical development.
• Clear communication in both Portuguese and English.

📍 Working Conditions

• Location: Lisbon
• Work model: Hybrid, 3 days per week in the office
• Experience: Around 2 years
• Languages: Portuguese C1 and English C1

🌟 Why Join?

• Develop modern Java microservices within an enterprise environment.
• Gain practical experience with REST and GraphQL APIs.
• Work with modern IAM technologies such as Keycloak, Okta, and OIDC.
• Strengthen your knowledge of code quality and application security through SonarQube and Snyk.
• Receive guidance from senior engineers.
• Participate in a structured technical upskilling programme.
• Build a strong foundation for progression toward a Mid-Level Backend Engineer position.