Backend Developer

Joining KEYES means giving purpose to your talent.

Are you looking for an environment where technology is not an end in itself, but a lever to build a sustainable future? At KEYES, we are not just looking for technical expertise; we are looking for people who share our values.

Do you want to continue your career and grow within one of Belgium’s leading IT companies?

Join KEYES as a Backend Developer

We support large enterprises, the public sector, healthcare organizations, and SMEs in all their digital challenges: Infrastructure & Cloud Solutions, Cybersecurity Solutions, Business Software Solutions, Mainframe Solutions, Data & AI Solutions, Advisory Solutions, and Staffing Solutions.

THE BACKGROUND

For our client, an EU Institution based in Brussels, we are looking for a Backend Software Engineer (Python/ Django) to join a long-term mission within an international team delivering modern digital services and business-critical applications.

You will contribute to the development, maintenance, and enhancement of backend services and APIs, ensuring secure, scalable, and high-performing applications that support key business processes.

Please note: candidates must be located within (2) two hours of Brussels, as regular onsite presence is required throughout the assignment.

YOUR MISSION

As a Backend Developer, your responsibilities will be as follows:

• Development of back-end website applications using Python and Django.

• Integration of user-facing elements developed by front-end developers with server-side logic.

• Implement core business logic using Python 3.11 and Django.

• Design and implementation of data storage solutions using relational databases and SQL.

• Apply data and security best practices: input validation, authentication/authorization, secure storage, compliant logging and monitoring.

• Optimization of applications for maximum speed, scalability, and reliability.

• Design and develop APIs and backend services.

• Participating in the design and creation of scalable software architectures.

• Maintenance of code integrity and organisation.

• Writing clean, functional, and maintainable code on the back-end.

• Compile and analyse data, processes, and code to troubleshoot problems and identify areas for improvement, including setting up and querying monitoring tools.

• Perform unit and integration testing, debug, fix, and validate code changes.

• Deliver solutions that fulfil functional and non-functional requirements and align with user expectations.

• Write technical documentation.

• Basic configuration of containerised environments and cloud-based services supporting back-end functionality.

• Develop and maintain services and business logic using Python, Django ORM, and asynchronous task-processing frameworks.

• Implement authentication and authorization mechanisms to secure APIs and services.

• Write and maintain unit and integration tests to ensure code quality and reliability, integrating them into CI/CD pipelines.

• #LI- MS1

  #TRASYS

YOUR PROFILE

• Bachelor's degree with at least 7 years of relevant professional experience, OR

• Master's degree with at least 5 years of relevant professional experience

• Ability to understand, speak, and write English (minimum B2 level)

Technical knowledge REQUIRED

• Strong experience with Python 3.11 development.

• Proven experience with Django 4.2+ and the Django ORM.

• Solid experience designing, developing, and maintaining REST APIs and backend services.

• Good knowledge of SQL and relational database design.

Technical knowledge PREFERRED

• Experience with asynchronous task-processing frameworks such as Celery, RabbitMQ, Faktory, or equivalent technologies.

• Experience with containerization technologies and modern deployment environments.

• Knowledge of code quality, linting, testing, and CI/CD practices.

• Understanding of authentication, authorization, and application security best practices.

• Experience troubleshooting complex backend applications and performance issues.

• Strong documentation and collaboration skills.

Soft skills

• Talent for attention to detail in code correctness, error handling, and documentation.

• Ability to analyse complex back-end issues and design effective solutions.

• Capability of integ