Senior Software Engineer

Legal AI is only as good as the knowledge behind it. At Lefebvre Sdu weve been building that knowledge for over 200 years. Day in day out. Law by law. Word by word. As the Dutch heart of Lefebvre Group the European leader in legal and tax knowledge were also developing our own platform: GenIA-L where lawyers and tax advisors dont just get an answer but an answer theyre willing to attach their name to. More than 75000 professionals use it daily generating over 100 million euros in ARR across Europe. Were looking for a Senior Software Engineer to help build that.

HOW YOULL MOVE US FORWARD

Were bringing separate knowledge portals together into one platform with AI as the primary way users interact with our platform. Were building GenIA-L: an agentic AI solution that understands and answers legal questions based on our own trusted content. With you on board the team will be able to take end-to-end ownership of its own practice the role is backend-first: youll take ownership of business-critical services around authentication authorization and user management along with components like PDF export and chat delivery via Redis. Ownership in this role at Lefebvre Sdu means actively driving continuous improvement stabilization and simplification of these systems: so you wont just be keeping the lights on. Frontend work will also come up so a solid frontend level is desired. The product is under active development so what you build and improve now will determine how stable and scalable this platform is a year from now.

WHAT WERE LOOKING FOR

Technical depth is a non-negotiable. You have extensive experience with TypeScript and preferably with authentication and authorization systems in production environments as this is the most important part of the role. Youre well-versed in OAuth 2.0 / OIDC flows and arent afraid to untangle complex system integrations around permissions and roles. You take ownership: youre comfortable with stakeholder management and proactively drive improvement simplification stabilization and documentation. Frontend doesnt need to be your greatest strength but you should be good enough at it to pick it up from time to time.

• TypeScript / and related frameworks (e.g. NestJS Koa)

• Authentication and authorization (OAuth 2.0 / OIDC)

• GraphQL / Apollo

• Relational databases (Postgres SQLite MariaDB) and Firebase

• Redis

• Docker CI/CD (GitHub Actions)

• AWS / Kubernetes / Helm is a strong plus

• Familiarity with ORMs (e.g. Prisma MikroORM)

• Familiarity with React /

WHAT YOURE SIGNING UP FOR

At Lefebvre Sdu youll work in an organization thats in the middle of a transformation and takes the public market seriously. Thats the direction and were making the journey together. Youll get the mandate the space and the colleagues to make it happen.

Youll join a team with a Product Owner three frontend developers a UX designer and a Scrum Master who also works across multiple teams. Youll have room to shape your role and help determine how we work with a clear shared goal: building the AI-first platform. Youll bring the backend experience the team needs to take real end-to-end ownership and youll report to the Lead Frontend Developer. Youll take part in the teams regular scrum rituals (dailies refinements retros planning) and have one-on-ones with your manager. Through the team youll also be an important point of contact for application administrators and customer support who need technical assistance so you should enjoy breaking down technical problems and communicating about them with less technical colleagues.

• A place where you have influence from day one: on the approach the processes and the direction.

• Colleagues who deliberately chose Lefebvre Sdu over big tech jobs because here theyre building something that doesnt exist yet.

• Salary between 5500 and 6450 per month based on a 36-hour week since thats full-time for us.

• A bonus tied to company performance: a fixed year-end bonus of 4% and profit sharing of up to 6%.

• 23 vacation days and a personal choice budget of 12% of which 8% is holiday pay and 4% is freely allocable. Want more vacation Just buy it.

• A solid pension plan through PGB including supplementary partner insurance.

• Collective insurance plans.

• A travel allowance of 0.25 per kilometer or a public transport reimbursement plus an attractive bike plan. For employees with a commute of less than 10 km or more than 60 km we have an adjusted arrangement.

• Two days a week in the office in The Hague within walking distance of Voorburg station. The rest of the week wherever you work best.

• Room to grow: in your craft in your role in the organization.

WANT TO KNOW MORE

Wed love to tell you all about the team and the role. Send us your CV and youll hear from us within a few business days. Have a few questions first Message or call Elize at .

A reference check and a VOG (certificate of good behaviour) are part of the selection process.