Senior Back-End Developer (F/M) Sophia-Antipolis/ Paris/Lyon/Krakow

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✨ Revolutionize Learning with LumApps! ✨

At LumApps, our mission is to create truly groundbreaking learning experiences.
Our motto: “More learning moments, better future.”

🔭 About LumApps Learning 🔭

As pioneers in mobile learning, Teach on Mars develops a next-generation digital training platform for companies.
Natively mobile and social, it leverages the latest advances in artificial intelligence to deliver relevant content to users every day and accelerate their skills development.
At the end of 2023, Teach on Mars joined LumApps, a B2B SaaS scale-up that builds innovative, integrated intranets for large European and international companies.
By becoming part of LumApps, Teach on Mars extends micro-learning to every employee, seamlessly embedded into the overall employee experience.

🌍 About LumApps 🌍

A SaaS platform dedicated to Employee Experience, engaging every employee through personalized communication, on any device, wherever they work, while connecting them with the tools, people, and information they need to be their most productive.
Our mission: to give employees a sense of belonging and purpose.
Trusted by 700+ enterprise customers worldwide.
A team of 600+ Lumies, spread across 11 offices: Lyon, Paris, Sophia-Antipolis, Lille, Barcelona, Hamburg, London, Austin, Tokyo, Zurich and Krakow.

🚀 The Role 🚀

As a Senior Back-end Developer, you will play a central role in shaping our technical solutions and ensuring the robustness of our SaaS platform.
We are looking for someone hands-on, with a strong track record of contributions (GitHub or similar) and proven experience in at least two of our core back-end technologies.

Your main responsibilities:

• Contribute to architecture decisions and technical design.
• Develop and maintain scalable, reliable back-end features.
• Design and implement APIs in close collaboration with the front-end and mobile teams.
• Write and maintain automated tests (unit, integration).
• Participate in code reviews and continuously improve best practices.
• Monitor, debug, and optimize services in production.
• Ensure that the codebase follows industry-leading standards and practices.

🌟 What we’re looking for 🌟

We need a strong technical profile, Senior or Senior+ level, who is entrepreneurial, pragmatic, and able to deliver end-to-end solutions in a collaborative environment.

You should bring:

• Proven expertise in at least 2 of our 3 main back-end technologies: PHP, C# .NET, Python.
• A strong track record of hands-on coding contributions (heavy GitHub commit history preferred).
• Professional proficiency in English (written and spoken).
• Solid software engineering foundations: clean code, maintainability, testing, scalability.
• Strong sense of ownership and autonomy, with the ability to make sound technical decisions.
• A collaborative and inclusive mindset, thriving in teamwork.

Nice-to-have:

• Experience with cloud platforms (AWS, GCP, Azure).
• Familiarity with containers and orchestration (Docker, Kubernetes).
• Knowledge of modern front-end frameworks (React, Angular).

💡 Our Tech Environment 💡

• Product: SaaS
• Back-end: PHP, C# .NET, Python
• Front-end: React, Angular
• Databases: PostgreSQL, MySQL
• Hosting: GCP & Azure
• Freedom of choice: OS & IDE

We aim to celebrate diversity and are committed to creating an inclusive environment for all employees.
We encourage applications from candidates of all backgrounds, identities, and experiences.