Senior Backend Developer (Python Backend) for NATO

Would you like to join the leading international intergovernmental organization

We are looking for a senior Python Backend contractor to support the modernization of existing applications as part of a broader platform transition. This is a highly hands-on role: the selected contractor must have strong practical experience and be able to contribute from day 1 with minimal ramp-up.

The main focus of this role is to refactor existing Python applications with minimal intervention to support the gradual decomposition of a monolith into a set of decoupled services while ensuring that configuration and settings are fully environment-based.

This is a delivery-focused role not a greenfield rewrite or architecture-only position. We are looking for an engineer who can assess the existing codebase quickly identify pragmatic refactoring opportunities and implement them directly.

Important: we will only consider candidates whose primary professional experience is as a Python Backend Engineer. Profiles coming mainly from adjacent roles with only partial backend exposure will not be considered

Key responsibilities:

• Refactor existing Python backend applications to support the decomposition of a monolith into smaller decoupled services.

• Identify pragmatic low-impact changes that improve modularity and separation of concerns without unnecessary redesign.

• Ensure application configuration and settings are environment-based and suitable for deployment across multiple environments.

• Develop and maintain production-grade backend services and APIs in Python with focus on maintainability reliability and security.

• Support the transition of applications toward containerized and automated deployment models working closely with DevSecOps and platform engineers.

• Improve code quality testing troubleshooting and documentation to enable safe incremental change.

• Troubleshoot and resolve functional integration and performance issues in existing backend services.

• Document implemented changes and contribute to good backend engineering practices across the team.

Essential Qualifications & Experience:

• 7 years of professional experience in backend software development with Python backend engineering as the main professional focus.

• Strong recent hands-on experience in Python backend development.

• Proven experience building and maintaining production backend services and APIs.

• Proven experience working in existing or legacy codebases and performing incremental refactoring.

• Practical experience supporting the decomposition of monolithic applications into smaller decoupled services.

• Strong understanding of environment-based configuration backend architecture API design and database design.

• Good understanding of integration patterns service boundaries and maintainable backend design.

• Familiarity with CI/CD practices Git workflows code reviews and Agile/Scrum delivery.

• Good understanding of secure coding practices and writing maintainable well-tested code.

• Strong analytical debugging communication and documentation skills.

• Experience with Docker and Kubernetes-based deployments.

• Experience with message queues event-driven architectures or caching strategies.

• Experience in cloud or hybrid environments.

• Good spoken and written English.

If youve read the description and feel this role is a great match wed love to hear from you! Click Apply for this job to be directed to a brief questionnaire. It should only take a few moments to complete and well be in touch promptly if your experience aligns with our needs.