Software Development Engineer
Software Engineering
Brussels, Belgium
Job description
Let’s shape the future of finance - together
At Isabel, we believe that real innovation happens when people and ideas connect
That’s why we’re building more than technology, we’re building an ecosystem.
One where every voice counts, and where your work can truly make a difference.
We’re looking for curious minds and collaborative builders. People who believe success means growing together, learning from each other, and challenging the status quo.
If that sounds like you, keep reading.
We are looking for a Java Developer to join our Isabel 6 and Trust Services delivery department. The team plays a crucial role in developing and enhancing our IntelliTrust platform, our in-house real-time transaction monitoring system. This is a unique opportunity to work on high-impact, mission-critical systems where your code directly supports core banking operations and provides a trusted and secure platform to our customers. You'll be part of an initiative that's central to our 2026-2027 strategic roadmap, with visible executive sponsorship and clear business value.
What You'll Be Working On: The Transaction Monitoring Enhancement Initiative
You'll contribute to building advanced payment processing and analysis capabilities including:
Real-time velocity detection: Monitoring transaction patterns to detect anomalies in frequency, amount, and behavior
Behavioral profiling engine: Processing customer transaction profiles to identify statistical deviations and pattern changes
AI/ML integration: Building data pipelines, feature engineering, and model integration for behavioral anomaly detection
Time-series analysis: Implementing dispatcher architectures and time-series database integrations for high-frequency transaction monitoring
Rule engine enhancements: Developing flexible, configurable analysis rules for amount deviations, pattern matching, beneficiary intelligence, and more
Event-driven architectures: Building queue-based systems for real-time transaction processing
Model deployment & monitoring: Implementing ML model serving infrastructure and monitoring model performance in production
What you’ll do
Development
Design, develop, and maintain Java-based microservices for transaction monitoring Implement real-time transaction processing capabilities with performance optimization
Build and integrate AI/ML models into production transaction monitoring workflows
Develop feature engineering pipelines to prepare transaction data for ML models
Implement model serving infrastructure for real-time prediction and scoring
Build configurable rule engines that empower business analysts to create detection rules autonomously
Integrate with AMQP-based message queues and external APIs
Write clean, maintainable, testable code following Clean Code principles
Apply BDD/TDD practices for comprehensive test coverage
Participate in code reviews, ensuring high-quality standards across the team
Contribute to technical design decisions and architecture discussions
DevOps & Deployment
Implement and maintain GitLab CI/CD pipelines for automated testing and deployment
Manage Kubernetes deployments and container orchestration
Deploy and manage applications across Dev, Acceptance, and Production environments
Monitor application and model performance, troubleshoot production issues
Implement logging, monitoring, and alerting for transaction monitoring systems
Collaborate with infrastructure team on containerization and scalability
Ensure code quality and security using Sonar, Fortify, and Mend
Collaboration & Teamwork
Work closely with business analysts and data scientists to understand monitoring requirements
Collaborate with architects on solution design
Partner with BI team on data availability and profiling requirements
Participate actively in Agile ceremonies (daily standups, reviews, retrospectives)
Share knowledge and mentor junior developers
Communicate technical concepts to non-technical stakeholders
Tech we use
Primary language: Java
Messaging: AMQP-based queuing systems
Architecture: Microservices/monolith, event-driven, domain-driven design, hexagonal architecture
Infrastructure: GitLab CI/CD, Kubernetes, OpenShift
Data: Time-series databases, PostgreSQL, Oracle, ML data pipelines
Testing: BDD/TDD practices, Postman, SoapUI, Gatling, RestAssured
Quality & Security: Sonar, Mend
Methodology: Agile Kanban
Job requirements
What makes you a great fit
Technical Foundation:
+3 years of professional Java development experience
AI Java developer with strong hands-on AI usage
Strong knowledge of Spring and Java ecosystem
Experience with RESTful APIs and microservices architecture
Understanding of relational databases (PostgreSQL and/or Oracle experience)
Messaging & Integration:
AMQP (RabbitMQ, ActiveMQ, or similar message queue systems)
Postman & Rest Assured for API testing and development
Experience with message-driven architectures and asynchronous processing
AI/ML Development Experience:
Hands-on experience integrating AI/ML models into development activities
Understanding of ML model lifecycle: training, validation, deployment, monitoring
Experience with feature engineering and data preparation for ML models
Familiarity with ML frameworks (scikit-learn, TensorFlow, PyTorch, or similar)
Knowledge of model serving approaches (REST APIs, batch prediction, real-time inference)
Experience working with data scientists to productionize ML prototypes
Understanding of Python for ML integration (basic to intermediate level)
Awareness of ML model performance metrics and monitoring techniques
DevOps & Container Orchestration:
Kubernetes for container orchestration and deployment
Understanding of containerization concepts (Docker)
Experience with CI/CD pipelines (GitLab CI, Jenkins, or similar)
Experience with Linux environments and shell scripting Monitoring and logging tools experience (ELK stack, Prometheus, Grafana, or similar)
Testing & Quality
BDD/TDD practices
Experience writing unit tests, integration tests, and acceptance tests
Familiarity with testing frameworks (JUnit, Cucumber, Mockito, or similar)
Code Quality Mindset:
Strong advocate for Clean Code principles
Understanding of SOLID principles and design patterns (hexagonal architecture)
Experience with code review processes and static code analysis tools
Commitment to writing self-documenting, maintainable code
Soft Skills:
Collaborative team player with excellent communication skills - fluent in English & Dutch or English & French
Agile mindset: adaptable, iterative, customer-focused
Proactive problem-solver who takes ownership
Ability to work effectively with cross-functional teams (analysts, architects, data scientists, infrastructure)
Comfortable working in a fast-paced environment with evolving requirements
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Willingness to learn and share knowledge
Nice to Have - Additional Technical Skills:
React for UI development
Node.js for JavaScript-based services
ForgeRock experience (identity and access management)
SoapUI for SOAP service testing
OIDC/OAuth2 implementation experience
Jenkins for CI/CD pipelines
Sonar, Fortify, Mend for code quality and security scanning
AI/ML & Data:
Experience with MLOps platforms (MLflow, Kubeflow, SageMaker, or similar)
Knowledge of feature stores (Feast, Tecton, or similar)
Experience with time-series databases (InfluxDB, TimescaleDB, Prometheus)
Understanding of real-time ML inference optimization techniques
Experience with A/B testing and model experimentation frameworks
Familiarity with data streaming for ML (Kafka Streams, Flink)
Experience with model monitoring and drift detection
Knowledge of explainable AI (XAI) techniques
Domain & Architecture:
Experience with event-driven architectures and domain-driven design
Experience with high-volume transaction processing systems
Financial services or banking domain knowledge
Why join us
At Isabel, we offer more than a job, we offer a place to grow, contribute, and thrive.
A human-sized Belgian company (250 people) where your ideas and impact matter
50% hybrid work, flexible hours, and autonomy to manage your time
Coaching, training, and tailored development paths for every career stage
A flat, collaborative structure with real ownership and cross-functional work
Competitive rewards: Flex Income Plan, annual bonus, insurance, meal vouchers
A strong engagement culture and inclusive mindset
Easy mobility options: our MOBI strategy supports flexible, low-footprint commuting, whether by bike, public transport, or electric car
Professional gatherings that encourage collaboration and networking, as well as fun and purposeful activities led by our BeFun team
A certified Top Employer with 30 years of tech leadership and ambition
Ready to join us?
Your voice, your vision, and your impact all have a place here.
Let’s shape smarter solutions and a stronger digital economy. Together.
- Brussels, Brussels, Belgium
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