
Senior Java Software Engineer
Take ownership of enterprise Java applications in Brussels - from development to support - within a mature integration-driven environment.
Job description
About Brainsquare
Brainsquare is an engineering-driven IT service company active in enterprise application development, integration and delivery governance.
We design, build and maintain business-critical applications for large organizations in Belgium. Our teams combine strong technical expertise with ownership and pragmatic delivery.
For a mission in Brussels, we are looking for a Senior Java Software Engineer (5+ years experience) to strengthen an enterprise application landscape.
Senior Java Software Engineer
Your mission:
As a Senior Java Software Engineer, you contribute to both project delivery and application maintenance within a business-critical environment.
You take ownership from analysis support to implementation, testing, documentation and operational follow-up.
Responsibilities
Development & Delivery
Contribute to and validate functional analysis and specifications.
Deliver IT changes and projects within scope, budget and planning.
Develop new components and enhance existing applications in line with standards.
Perform code reviews and support release management.
Test developments before handover to key users.
Document technical implementations and user guidelines.
Application Maintenance & Support
Handle application tickets for owned systems.
Perform bug fixing and root cause analysis.
Propose structural improvements.
Maintain documentation and implement approved enhancements.
Support business users and define response/availability agreements.
Participate in support rotations if required.
Collaboration
Work closely with IT colleagues and business stakeholders.
Report progress transparently.
Contribute actively to team meetings.
Propose improvements that reduce Total Cost of Ownership (TCO).
Job requirements
Requirements (Senior Profile)
5+ years of experience as Java Software Engineer
Degree in IT or equivalent experience
Experience working in Agile/Scrum environments
Strong ownership mindset
Comfortable working under deadlines
Languages: English + Dutch or French
Technical Stack
Core
Java (7/8/11/17)
Spring Framework
Microsoft SQL Server
Glassfish 3.1 / Wildfly
ActiveMQ / OpenMQ
Montova ESB
SOAP / RMI / REST
RESTful web services
Concurrency & multithreading
Frontend / Additional Exposure
ReactJS, Redux, ES6
C#
JSON / XML
Linux / Unix basics
Toolchain
Maven, Jenkins
Git / Bitbucket, Jira
BuildMaster / Octopus
Eclipse / IntelliJ
SoapUI, ReadyAPI, SSMS
Nice to Have
Kubernetes, Docker, containerization
Cloud platforms (AWS / Azure / GCP)
Security best practices and protocols
Security Mindset
You write clean, secure code and understand topics such as:
OWASP vulnerabilities
Authentication & authorization (OAuth, JWT, SAML)
Encryption (at rest & in transit)
API security
Dependency and vulnerability management
Why Choose Brainsquare
Work in a mature enterprise environment with real ownership.
Clear scope and responsibilities.
Professional and efficient decision-making process.
Collaboration with experienced engineers.
Contract options: employee or freelance.
Start date: ASAP.
Our Selection Process
Our selection process consists of a maximum of three interviews (technical and team discussions).
After that, a decision is taken promptly. If you are ready to step into a senior role with immediate impact and clear ownership, we encourage you to apply today.
or
- Brussel (Brussels, Belgium)
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