Senior Software Engineer (H/F)

France | Oct. 30, 2026

Report as Closed

Company: Hello Watt

Country: France

Salary: $61,692 - $89,733

Type: Hybrid remote

Employment: Full-time

Description: The Hello Watt app has 3 million downloads, 1 million homes connected. This is the app to manage energy in your home, reduce bills and contribute to the stability of the electricity network via flexibility markets - we are looking for a Senior Software Engineer who is equally comfortable with Django and React to help us accelerate, connect to more manufacturers and improve the impact of the application. You will be at the heart of its development on all web/iOS/Android platforms. At Hello Watt, we are convinced that AI is profoundly transforming the developer profession. We are looking for engineers enthusiastic about the idea of exploring and defining, together, the contours of what our new developer profession will be tomorrow. Your missions: - Implement new functionalities on the Hello Watt application (web/iOS/Android) - Develop API integrations for device control: solar inverters, thermostats, electric vehicle charging stations - Integrate energy flexibility and load-response functionalities (intelligent programming, control according to power signals). solar production/grid voltage, etc.).- Maintain a high level of quality on the code, whether hand-written or generated by AI through demanding reviews, robust testing and the implementation of tools to improve the AI agents.- Actively contribute to the team's AI tooling and workflows: shared prompts and conventions, guardrails, quality gates and feedback loops to continuously improve the quality of the generated code- Design the evolution of the architecture of the platformProfile soughtIn the era where AI accelerates code production, we are looking for engineers who are not only focused on implementation: asking the right problems, understanding users, and maintaining the architecture over the long term. Key skills sought:- Problem solving: ability to break down complex problems, identify the real business issues and make the right technical compromises- User & UX focus: strong sensitivity to the user experience and the value delivered- System architecture: system vision, ability to design and develop a modular, scalable and maintainable web architecture - AI-native mindset: advanced practice of AI tools for development, critical thinking on their outputs, and desire to contribute to elevating the practice of the entire team Technical skills sought: - Confirmed experience in web development with python (Django, Flask, Sanic, FastAPI.) and with a javascript framework (React, Vue, Angular.) - At least 5 years of experience in a similar position, within a work environment putting user experience at the heart of concerns - Mastery of good development practices: code typing & lint, unit and functional tests, documentation, code reviews, modular architecture by business domains Other skills sought: - Willingness to work on impactful products - Taste for beautiful things - Willingness to progress, individually and as a team - Enthusiasm to explore how AI can elevate our profession, our products and our workflows Technical environment: Backend - Language & Frameworks: Python with Django (REST APIs, ORM, Admin) - Task orchestration: Celery - Cache: Redis Frontend Web - Language: TypeScript / JavaScript - Framework: ReactJs - Styling: Design System Hello Watt + Tailwind CSS - Hybrid approach: Webviews integrated via CapacitorJS (iOS/Android compatibility) - Code sharing: Reuse of native web code Database - SQL: MySQL for relational data - NoSQL: MongoDB for managing semi-structured data / documentsInfrastructure & Deployment - Cloud Provider: AWS (Elastic Beanstalk, S3, RDS, etc.) - CI/CD: GitLab CI for automated integration and deploymentTools & Collaboration - Project management: Linear (task tracking, product roadmap) - Documentation: Slite - Version control: GitLab Do you want to work on multiple projects where the production of your work is rapid? Do you want to join a Greentech working on cutting-edge products in Europe? Do you want to use data to offer services to reduce the carbon footprint and energy bills? Look no further, come to Hello Watt! Our values: - Impact more: we support individuals in the energy transition and we use technology to enable them to control their consumption. We aim big to maximize this impact. - User focused: listening to our customers, we seek to surprise them with the quality of our services and our products. - One caring team: we ensure the well-being and development of each person by basing our relationships on humility and honesty.

Apply here:

Web: Apply here

Emails: