Back-End Engineer H/F - Flexcity

Are you passionate about energy, sustainability, and technology, with a drive to create impactful backend solutions?

Flexcity, a leading European energy tech company within the Veolia Group is looking for a resourceful Senior Backend Developer to join our Technology department.

At Flexcity, Tech is not a support function - it is a key business driver. We operate in a complex, real-time, and highly regulated environment, requiring robust, secure, and adaptable systems to manage the increasing volatility of energy markets.

We structure our Tech organization into Feature Teams focused on delivering product value, and Platform Teams that provide the internal services and tooling enabling them to move faster and more reliably.

Our Market, Strategy, Connect, and BI Feature Teams work end-to-end on user-facing capabilities with a high level of ownership and autonomy.

Our Infrastructure, Security, IT, and Data Platform Teams build and maintain the core services, tooling, and foundations that empower the entire organization.

Teams are small, autonomous and operate with a strong sense of ownership. Guilds complement this setup by creating spaces for engineers to share expertise, align on standards, and contribute to our long-term technical vision across the company.As part of the team, you will participate in design discussions and implement new features aligned with user and business needs. You will work closely with an Engineering Manager and a Product Manager, and your role will generally cover three areas:

- Backend Development - 80%

- Design, develop, test, deploy, monitor and support backend services.
- You will contribute across the entire development lifecycle and ensure robustness, scalability and reliability in production.
- Team Improvement - 10%

- Help improve workflows, coding standards, documentation and engineering practices.
- You will play an active role in fostering a culture of collaboration and continuous improvement.
- Tech Holder - 10%

- Partner with the Product Manager to align on scope, feasibility and delivery timelines.
- You will provide technical guidance within your domain and ensure features are built with long-term quality and consistency.

As a member of Flexcity's Tech department, you will gain hands-on experience in developing production-grade applications in the energy sector within a modern agile development team. You will work with cutting-edge and innovative technologies used by Flexcity.

Technical stack

We use a modern, well-crafted tech stack that emphasizes clean architecture, reliability and developer excellence.

- Languages: Kotlin + SpringBoot, Go, Python
- Hexagonal architecture / Domain-Driven Design (DDD)
- Google Cloud Platform (GCP) / Kubernetes
- Pub/Sub
- PostgreSQL
- React
- GitLab
- Grafana Observability Stack

Hard Skills

- Fluent in French, Professional English
- Proficient in backend development: Expertise in building robust and scalable back-end solutions.
- Software architecture: Understanding of scalable, maintainable architecture principles.
- Domain-driven design (DDD) & hexagonal architecture: Familiarity with advanced architectural patterns to design modular and decoupled systems.

Soft Skills

- Strong communication skills: Effectively convey complex technical concepts to both technical and non-technical stakeholders, fostering collaboration and understanding across teams.
- Mentoring and coaching: Guide and support junior engineers, sharing knowledge and best practices to help them grow and succeed within the team.
- A positive, pragmatic and professional attitude
- Comfortable in a fast changing work environment, you can easily adapt