Lead Fullstack Engineer

About the role

You will own the technical delivery and long-term success of digital products for high-profile clients by shaping resilient architectures and sustainable engineering practices. You will partner closely with product managers and stakeholders to translate business needs into robust technical backlogs and clear specifications. Your leadership will ensure that each project meets extreme quality standards while accelerating delivery through the smart use of AI and automation. You will mentor junior engineers, elevate the entire team's skills, and foster a culture of continuous learning and improvement. Ultimately, you will be a key driver in modernizing legacy systems and pushing the boundaries of what is possible in applied software engineering.

Key facts

What you'll do

Coordinate the technical delivery of innovative digital products by defining resilient architectures and driving high-quality implementation from initial concept to production deployment.

Define and maintain clear technical specifications and architecture diagrams that enable the development of robust features without bugs or regressions.

Establish and enforce a quality strategy centered on Clean Code, automated testing, and systematic code reviews to ensure long-term maintainability.

Implement structured work environments based on the 5S methodology to maximize organization, clarity, and team efficiency.

Leverage AI tooling and intelligent automation to significantly accelerate development cycles and deployment speed.

Act as the primary technical partner for the client, participating in all project rituals such as backlog refinement, daily stand-ups, and key ceremonies.

Explain and defend technical decisions to build trust and align all stakeholders around a shared vision and realistic goals.

Create the conditions for high team performance by setting up effective problem-resolution loops through daily problem-solving sessions.

Enable the team to harness the power of Large Language Models to boost individual productivity and innovation.

Analyze root causes of defects and drive knowledge sharing sessions to elevate the overall expertise and capabilities of the engineering squad.

Formally mentor and coach software engineers through pair programming, constructive code reviews, and tailored learning opportunities.

Continuously evaluate and adopt new practices that allow the team to deliver value faster while maintaining the highest standards of quality.

Adapt your leadership style to the specific needs of each project, whether it involves migrating legacy platforms or building innovative features from scratch.

Champion the evolution of technical practices within Theodo by contributing to internal communities of excellence and sharing best practices.

Requirements

Bring more than 8 years of hands-on experience in software development, with a strong track record of delivering complex digital products.

Demonstrate deep expertise in both frontend and backend technologies, allowing you to understand trade-offs and guide full-stack implementation decisions.

Possess a solid understanding of software architecture principles and the ability to design systems that are scalable, resilient, and maintainable.

Show proven ability to lead and mentor other engineers, fostering a collaborative environment where knowledge sharing is the norm.

Have experience working in an Agile environment, facilitating ceremonies and driving continuous improvement within the team.

Exhibit strong problem-solving skills, with a data-driven mindset and the capacity to make informed decisions under pressure.

Communicate effectively in both written and verbal French, ensuring clarity and precision when interacting with clients and stakeholders.

Be fully committed to the project on a permanent, full-time basis, aligning your schedule with the demands of fast-paced digital product development.

Practical notes

The role is based in Paris, France, requiring your physical presence in the office.

You will be integrated into a permanent contract (CDI) with Theodo, offering long-term career development within a growing group.

Travel is generally not required for this position, as the role focuses on local client engagements in the Paris region.

Candidates must meet all stated requirements without exception, as the profile is tailored to the specific needs of our demanding client projects.

Theodo is an equal opportunity employer, welcoming applications from professionals of all backgrounds.

Applications will be reviewed continuously, and the position will remain open until filled by a candidate who matches the outlined profile.

The fast-paced nature of this role requires a high level of adaptability and dedication to continuous learning.

You will be expected to actively participate in Theodo's community of practice, contributing to the collective knowledge and engineering excellence across the group.

This position offers the chance to work on impactful projects for renowned clients such as Qonto, Doctolib, Carrefour, and Pernod Ricard.

Mastery of modern JavaScript ecosystems, including frameworks like React and NestJS, is essential for success in this role.

Experience with AI-assisted development tools and prompt engineering will be a significant advantage in optimizing team performance.

Your work will directly influence Theodo's strategic direction in AI Modernisation, helping shape the future of software engineering for the group.