Senior Java Full Stack Developer

Mission Overview

We are seeking a Senior Java Full Stack Developer for a consultancy mission at a client site, representing Keystone Solutions. In this role, you will develop, program, test, and maintain software applications to ensure they meet business needs and expectations.

• Participate in determining user needs and conduct feasibility analysis to understand requirements and assess technical feasibility for smooth application programming.
• Perform technical analysis and document changes and developments related to assigned applications to facilitate future modifications.
• Test solutions designed within the department and make necessary adjustments to ensure compliance with quality standards and business needs.
• Monitor production developments and make modifications as needed, contributing to the realization and improvement of assigned applications for an efficient development process.
• Control, analyze, and resolve intervention requests and bugs related to assigned applications to ensure optimal functionality.
• Act as a technical advisor for support and functional questions regarding software applications and management software, providing support for optimal use and development of various applications.

• Understand client requests and needs, critically analyze them (what, why, who, when, where, and how), and maintain a critical, analytical, and creative approach.
• Comprehend various database modeling concepts and object-oriented programming.
• Ability to work across the entire technical backend chain and the technologies used.
• Strong expertise in JAVA 8+ (Reactive Streams, performance, etc.) and associated frameworks (primarily Spring and Maven).
• Good knowledge of components such as Jenkins, JIRA, Git. Experience in implementing microservices and database queries (Oracle, SQL, and DB2) is a plus.
• Document applications for which you are responsible (e.g., user manuals, processes, etc.).
• Participate in the Agile way of life of the team (SCRUM Methodology).
• Develop and test new features or bug fixes in JAVA following existing patterns.
• Test your own work or that of a team member and support the business in data usage.
• Conduct technical analyses and challenge business analyses.
• Adhere to governance and IT strategy.
• Master's degree, Bachelor's degree, or equivalent experience.
• Minimum of 5 years of professional experience.
• Concrete experience in JAVA analysis and development (preferably Spring and Reactive Streams).
• Good knowledge of Git, Jenkins, and JIRA components.
• Good knowledge of databases (Oracle, SQL, DB2, etc.).
• Familiarity with IDEs like IntelliJ or similar.
• Good frontend experience with the latest versions of Angular (React is a plus).
• Comfortable with concepts such as ngrx, openid connect, HTML, CSS, Type Script, and SASS.
• Knowledge of Json Form is also an asset.
• Good knowledge of French or Dutch (oral/written) and knowledge of English (oral/written).
• Oral comprehension of French is an asset (French-speaking team).

• Synthesis skills and good organizational sense.
• Proactive in work and seeking new solutions.
• Autonomous.
• Rigorous.
• Good communication skills.
• Listening skills.
• Self-taught.

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

01/08/2026 - 31/12/2026 (5 months, full time)

• Agile – Level: Intermediate – Most recent:
  Any time
• Angular – Level: Expert – Most recent:
  Any time
• Java – Level: Expert – Most recent:
  Any time
• Jira – Level: Intermediate – Most recent:
  Any time
• Microservices – Level: Advanced – Most recent:
  Any time
• React – Level: Expert – Most recent:
  Any time

Dutch or French (Native or bilingual proficiency)

English (Professional working proficiency)