*Mission Overview:*
This is a consultancy mission through Keystone Solutions to support our clients Agile transformation within their enterprise digital channels. As a Keystone Solutions consultant, you will work closely with the clients multi-disciplinary squads that own end-to-end products for enterprise customers, developing and maintaining web and mobile solutions backed by cloud-based services. You will contribute to features across the stack (including backend services and integrations) while collaborating in an Agile, DevOps-oriented environment.
*Assignment Details:*
Role: Back-end Developer (Java)
Model: Keystone Solutions consultancy mission, working on-site with the client
Location: Brussels, Belgium (on-site at the client)
Team: You will join an Agile squad composed of internal and external members, with responsibilities spanning both development and operations.
*Key Responsibilities:*
Translate requirements into high-quality code as a Keystone Solutions consultant embedded with the client.
Design, build, and maintain high-performance, reusable, and reliable applications.
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- Backend focus: Java and Spring Framework (this will be most of your activities).
Collaborate with cross-functional teams to ship new features.
Work with outside data sources and APIs.
Ensure the best possible performance, quality, and responsiveness of the application.
Apply development best practices to ensure the quality of your code.
Identify and correct bottlenecks and fix bugs.
Be involved in Ops activities, including the setup of CI/CD pipelines.
Contribute to features end-to-end across the clients digital ecosystem (web, mobile, cloud backend).
*Language and Education Requirements:*
English: Sound knowledge of English is required. Knowledge of French or Dutch is a plus.
Education: Bachelor/Master or equivalent by experience.
*Agile Mindset:*
A positive attitude and pragmatism.
Thirst for knowledge: Agile is about learning and adapting. Knowledge sharing is key to success.
The goal of team success: Agile is about the success of the team, not individual heroics. It is more important for the team to succeed than for an individual to complete their own tasks.
There is no failure, only feedback: take everything as lessons, adjust actions based on feedback, and continuously improve.
Beyond roles: Agile teams are cross-functional. All required disciplines are represented in the team (analysis, development, testing, etc.). Although team members have a primary role, they are expected to take on other roles and contribute to other disciplines whenever it helps reach the sprint goal.
*Required Experience and Knowledge:*
At least 6 years of relevant experience.
You are a Software Craftsman who sees software development as a craft.
You know the principles of clean code and apply them effectively.
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Understanding of OO principles, DDD, design patterns, and best practices such as SOLID principles.
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You write readable code and perform refactoring where necessary.
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You are familiar with Test Driven Development (TDD) and have practical experience with it.
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Willing to pair.
*Technical Skills (Mandatory):*
Proven knowledge of Java, Spring, Maven, and databases.
Proven knowledge of RESTful APIs with Swagger (YAML).
Proven knowledge of version control systems (Git).
Proven knowledge of Continuous Integration/Deployment principles (Jenkins or alternative).
Proven knowledge of SAST (such as SonarQube, Fortify, NexusIQ or alternatives).
Knowledge of Docker, containers, and Groovy.
Participation in API automation testing as part of your development activities.
*Nice to Have:*
React
Node.js
Business experience: preferable
Specific requirement for Agile: practical experience with Scrum
*Soft Skills:*
Actively share knowledge with other developers (practices, technical topics) and suggest improvements to squad members; constantly seek to improve the squads way of working.
Easily adapt and bond with new colleagues.
Collaboration and feedback are key elements of your personality.
Dare to challenge requirements based on your expertise.
*Consultancy Nature of Work with Keystone Solutions:*
You will be a Keystone Solutions consultant, operating on-site with the client within their Agile squads.
You will collaborate closely with client stakeholders while being supported by Keystone Solutions expert community, methodologies, and delivery standards.
Your work will follow the clients context and priorities, with Keystone Solutions ensuring quality, craftsmanship, and continuous improvement in every engagement.
*Dynamic Projects Across Clients:*
Engage with complex, real-world challenges in enterprise-grade environments.
Build resilient backend services and integrations that power high-usage digital channels.
Following this mission, you will have opportunities to contribute to other strategic client projects through Keystone Solutions, broadening your impact and experience.
*Turbo-Charged Learning and Development:*
Access to peer coaching, knowledge-sharing sessions, and expert communities at Keystone Solutions.
Support for certifications and mastery of modern engineering practices (Clean Code, TDD, CI/CD, Cloud, Security).
Personalized growth plans aligned with your technical ambitions and consulting path.
*Ambition Skyrocketing within a Consultancy Framework:*
Accelerate your career by delivering measurable impact across varied client contexts.
Take on increasing scope: from feature ownership to architecture contributions and DevOps improvements.
Develop as a trusted advisor while staying hands-on with code and delivery excellence.
*Keystone Solutions Values in Action:*
Craftsmanship: we build clean, maintainable, and secure software.
Ownership: we take responsibility end-to-end, from design to operations.
Client Impact: we focus on outcomes that matter for users and the business.
Team Spirit: we succeed together through feedback, pairing, and knowledge sharing.
Curiosity and Integrity: we learn continuously and act with transparency.
Being a K‑Stone means bringing these values to each client project, every day.
*Role-Specific Consulting Opportunity:*
As a Senior Java Backend Developer, you will apply your expertise in Java, Spring, APIs, CI/CD, and SAST to elevate the clients digital products while leveraging Keystone Solutions consulting toolkit.
You will strengthen Agile and DevOps practices within the squad, contribute to automation and quality gates, and mentor peers through pairing and code reviews.
Your E2E mindset and clean code approach will help the client deliver robust, scalable, and secure enterprise features.
If you are ready to tackle technical and strategic challenges in a dynamic consultancy environment, apply today at Keystone Solutions Career Portal.