Junior Full Stack Developer Consultant

Mission Overview:

As part of a consultancy mission at a client site representing Keystone Solutions, we are looking for a Junior Full Stack Developer to strengthen existing delivery teams involved in the development, integration, and evolution of critical public sector digital services.

The initiative aims to support the digital transformation of public administrations through the implementation of interoperable, secure, and scalable solutions facilitating collaboration and information exchange between organizations. The program includes the development of new functionalities, the enhancement of existing platforms, and the adoption of modern software engineering practices.

Key Activities:

• Development and maintenance of business-critical applications and shared services.
• Integration with internal and external systems through APIs and service-oriented architectures.
• Modernization, optimization, and continuous improvement of existing applications and technical platforms.
• Contribution to the implementation of secure and resilient digital services supporting public sector organizations.

Languages:

French or Dutch: Expert level
English: Working proficiency

Responsibilities:

• Development and maintenance of business applications and shared digital services.
• Development of application components, APIs, and web services.
• Contribute to the design of application architecture and technical building blocks in collaboration with technical leads and solution architects.
• Participate in technical workshops, Agile/Scrum ceremonies, and stakeholder meetings.
• Support testing activities, technical documentation, deployments, quality assurance, monitoring, reporting, and continuous improvement initiatives.
• Collaborate with multidisciplinary teams to ensure alignment with business and technical requirements.
• Ensure adherence to security, performance, interoperability, and quality standards.

Experience:

• Minimum 3+ years of professional experience in Java software development.
• Experience working in complex multi-system environments and large-scale digital transformation projects.
• Experience in public sector environments is considered an asset.
• Proven experience in Agile delivery environments.

Competencies:

• Technical knowledge and practical experience of the following technologies:
• Java >= 21 and Spring Framework (Core, JDBC, Data, Security, AOP)
• JPA / Hibernate
• RESTful Web Services
• OpenAPI / Swagger
• Keycloak, Lombok, MapStruct
• SOA, Backend-for-Frontend, CQRS
• Test-driven development (JUnit, Mockito, Spring Test, Cypress)
• Angular 20
• Maven
• Docker
• OpenShift / Kubernetes
• Git and GitLab CI/CD
• SonarQube
• NPM
• OAuth 2.0
• Flyway or Liquibase
• PostgreSQL, SQL Server and relational databases
• BPMN and UML
• Jira and Confluence
• Agile/Scrum methodologies
• Continuous Integration and Continuous Delivery (CI/CD)

Soft Skills:

• Strong analytical and problem-solving skills.
• Ability to quickly understand and maintain existing codebases.
• Customer and solution-oriented mindset.
• Team player with strong communication skills.
• Autonomous, proactive, and quality-focused.

Mission & Working Conditions:

The mission is carried out within a hybrid working environment. Regular presence on site may be required depending on project needs and team activities. Collaboration with multidisciplinary teams across different public sector organizations.

If you are ready to tackle technical and strategic challenges in a dynamic consultancy environment, apply today at Keystone Solutions Career Portal .

Duration: As soon as possible - 31/12/2026 4 months • (full time)

Skills required:

• Agile / Scrum - Level: Junior - Most recent: Any time
• Angular 17 - Level: Junior - Most recent: Any time
• Docker - Level: Junior - Most recent: Any time
• Java 11 + 17 - Level: Junior - Most recent: Any time
• JMS - Level: Junior - Most recent: Any time
• JPA - Level: Junior - Most recent: Any time
• Oracle - Level: Junior - Most recent: Any time
• REST - Level: Junior - Most recent: Any time
• Spring - Level: Junior - Most recent: Any time
• Springboot 2.x + springboot3 - Level: Junior - Most recent: Any time
• SQL - Level: Junior - Most recent: Any time
• test metghodologiën - Level: Junior - Most recent: Any time
• Weblogic - Level: Junior - Most recent: Any time

Language requirements:

French or Dutch: Expert level
English: Working proficiency

Responsibilities

Development and maintenance of business applications and shared digital services.
Development of application components, APIs, and web services.
Contribute to the design of application architecture and technical building blocks in laboration with technical leads and solution architects.
Participate in technical workshops, Agile/Scrum ceremonies, and stakeholder meetings.
Support testing activities, technical documentation, deployments, quality assurance, monitoring, reporting, and continuous improvement initiatives.
Collaborate with multidisciplinary teams to ensure alignment with business and technical requirements.
Ensure adherence to security, performance, interoperability, and quality standards.

Experience

Minimum 3 years of professional experience in Java software development.
Experience working in complex multi-system environments and large-scale digital transformation projects.
Experience in public sector environments is considered an asset.
Proven experience in Agile delivery environments.

Competencies

Technical knowledge and practical experience of the following technologies:

Java >= 21 and Spring Framework (Core, JDBC, Data, Security, AOP)
JPA / Hibernate
RESTful Web Services
OpenAPI / Swagger
Keycloak, Lombok, MapStruct
SOA, Backend-for-Frontend, CQRS
Test-driven development (JUnit, Mockito, Spring Test, Cypress)
Angular 20
Maven
Docker
OpenShift / Kubernetes
Git and GitLab CI/CD
SonarQube
NPM
OAuth 2.0
Flyway or Liquibase
PostgreSQL, SQL Server and relational databases
BPMN and UML
Jira and Confluence
Agile/Scrum methodologies
Continuous Integration and Continuous Delivery (CI/CD)

Soft Skills

Strong analytical and problem-solving skills.
Ability to quickly understand and maintain existing codebases.
Customer and solution-oriented mindset.
Team player with strong communication skills.
Autonomous, proactive, and quality-focused.

Mission & Working Conditions

The mission is carried out within a hybrid working environment.
Regular presence on site may be required depending on project needs and team activities.
Collaboration with multidisciplinary teams across different public sector organizations.
Long-term assignment with potential extensions according to project evolution.

View more