Back End Software Engineer

Uni Systems; Brussel Hoofdstad; On-site; EUR 70,000 - 110,000; Full time

Job summary

Uni Systems is seeking a Back End Software Engineer to join the UniQue team in Brussels. You will develop and maintain backend web applications, design robust APIs, and ensure secure, scalable cloud services.

The role requires strong Python skills, experience with frameworks and databases, and a focus on observability, security and CI/CD practices. Collaboration across teams is essential to deliver high-quality software.

Qualifications

• Bachelor/Master degree or equivalent with extensive IT experience.
• Backend development with Python; Spring Boot and Hibernate are a plus.
• Experience designing RESTful APIs and web services.
• Familiarity with APM tools and OpenTelemetry for observability.
• Strong SQL skills with PostgreSQL, Oracle or MySQL; NoSQL knowledge helpful.
• Version control (Git) and CI/CD practices; Docker/Kubernetes exposure.
• Knowledge of OAuth2, OpenID Connect, JWT; EU Login understanding.
• Experience with i2 technology stack and modern security practices.

Responsibilities

• Develop and maintain backend web applications, services and logic.
• Design and optimize APIs, server-side functionality, and data storage.
• Integrate front-end components with backend systems and databases.
• Ensure security, performance, scalability and reliability in cloud environments.
• Implement authentication/authorization, logging, monitoring, and CI/CD tests.
• Create technical documentation and contribute to software design reviews.

Education

Master’s degree (EQF 7) with 5+ years IT experience

Bachelor’s degree (EQF 6) with 7+ years IT experience

Secondary education diploma with 12+ years IT experience

Tools

Git

Docker

Kubernetes

OpenAPI/Swagger

Dynatrace

Splunk

Elastic APM

OpenTelemetry

Job description

At Uni Systems, we are working towards turning digital visions into reality. We are continuously growing and we are looking for a Back End Software Engineer to join our UniQue team.

What will you be doing in this role?

• Develop and maintain back-end web applications, services, and business logic.
• Design, develop, and optimize APIs and server-side functionality.
• Integrate front-end components with back-end systems and databases.
• Design and implement efficient, scalable, and secure data storage solutions.
• Apply security best practices, including input validation, authentication, authorization, secure storage, logging, and monitoring.
• Ensure application performance, scalability, and reliability through continuous optimization.
• Participate in the design and development of scalable software solutions.
• Maintain clean, organized, and high-quality code following established coding standards.
• Analyze, troubleshoot, and resolve application issues through code review, monitoring, and debugging.
• Perform unit and integration testing, validate code changes, and ensure software quality.
• Deliver solutions that meet functional and non-functional requirements and user expectations.
• Create and maintain technical documentation.
• Configure and support cloud-based back-end services, including serverless functions, storage services, and managed Kubernetes environments.
• Implement and maintain authentication and authorization mechanisms to secure APIs and services.
• Develop and maintain automated unit and integration tests within CI/CD pipelines.

What do you need to succeed in this position?

• Minimum Master’s degree (EQF Level 7) with at least 5 years of IT experience, a Bachelor’s degree (EQF Level 6) with at least 7 years of IT experience, or a secondary education diploma granting access to higher education with at least 12 years of professional IT experience.
• Proficiency in back-end development with Python and experience working with frameworks such as Spring Boot, Hibernate, and Node.js.
• Strong understanding of the full web development lifecycle, programming concepts, development tools, and best practices.
• Experience with Application Performance Monitoring (APM) tools such as Dynatrace, Splunk, and Elastic APM, with knowledge of OpenTelemetry for metrics, logs, and distributed tracing.
• Strong experience with relational databases, including PostgreSQL, Oracle, and MySQL, with the ability to write complex SQL queries and design efficient database structures.
• Knowledge of NoSQL databases such as MongoDB, CouchDB, and Cosmos DB, including consistency and performance considerations.
• Experience with version control systems and development workflows, including GitFlow, trunk-based development, and exposure to legacy systems using SVN.
• Experience designing, developing, documenting, and securing RESTful APIs and web services, including the use of OpenAPI/Swagger.
• Knowledge of containerization and orchestration technologies such as Docker and Kubernetes.
• Understanding of authentication and authorization standards, including OAuth 2.0, OpenID Connect (OIDC), JWT, and EU Login.
• Experience working with and strong understanding of the i2 technology stack.

One of the following or an equivalent certification:

• AWS Certified Developer
• Associate, Microsoft Azure Developer Associate, or CNCF Certified Kubernetes
• Application Developer (CKAD).

At Uni Systems, we are providing equal employment opportunities and banning any form of discrimination on grounds of gender, religion, race, color, nationality, disability, social class, political beliefs, age, marital status, sexual orientation or any other characteristics. Take a look at Diversity, Equality & Inclusion Policy for more information.