We’re looking for a hands-on Full-Stack Developer to build and scale the internal tools and AI-powered applications that support Merkle’s delivery. You’ll own the application layer end-to-end - from the backend up through the frontend - covering backend logic, infrastructure, authentication, deployments, and day-to-day stability.
- Location: Rotterdam
- Full time
- Fixed Term Contract (Fixed Term)
What You’ll Do
- Own and maintain the full application stack across our internal tools: backend, database, auth, and frontend
- Design and implement authentication and access control (e.g., SSO with SAML or Okta, multi-tenant data isolation, role-based access)
- Write and maintain database schemas, migrations, and access policies (e.g., PostgreSQL with RLS and RPC functions)
- Build and manage serverless backend functions (e.g., for application logic and API integrations)
- Set up and maintain CI/CD pipelines and manage deployments across environments (e.g., DEV, UAT, PROD)
- Build and maintain modern frontends (e.g., React, Vite, TypeScript)
- Debug and resolve issues across the stack (e.g., build errors, networking, misconfigured services, 5xx errors)
- Collaborate with the AI/LLM side of the team to integrate model outputs cleanly into the application
- Take ownership from idea → build → run → improve
What You Bring
- 3+ years in software engineering (full-stack, AI, or platform development)
- Experience with modern JavaScript/TypeScript stacks (React, Next.js, Node.js), frontend and backend
- Experience with Docker and self-hosted infrastructure, not just managed cloud services
- Knowledge and experience with multi-tenant application patterns
- Solid problem-solving skills and strong ownership mindset
Strong advantage:
- Familiarity with backend-as-a-service platforms (e.g., Supabase, Firebase) for auth, database, storage, and serverless functions
- Exposure to alternative JS/TS runtimes (e.g., Deno, Bun)
Nice to Have
- Hands-on experience with LLM APIs (e.g., OpenAI, Anthropic)
- Familiarity with SSE streaming or real-time data patterns
- Familiarity with MarTech platforms (e.g., Adobe, Salesforce, CDPs)
- Experience with authentication systems (e.g., OAuth2, SAML, SSO)
Why This Role
- Build products, not projects
- Direct impact on how Merkle delivers at scale
- Work at the intersection of AI, engineering, and platform thinking
- High ownership and room to shape solutions
What We Offer
- A dynamic, international work environment with colleagues from around the globe.
- A challenging position at a successful company in a growing market.
- A fun and inclusive culture-think foosball, table tennis, themed events, and team parties.
- 3 extra days off (yes, at Merkle we take your well-being very seriously) - in addition to 25 annual vacation days, there are 3 Well-being Days.
- 2 Social Impact Days - you can volunteer for a charity of your choice.
- Extensive learning and development opportunities, including a wide range of personal and online training.
- A hybrid work model, with 2-3 days in the office and the rest working from home.
- A competitive salary and excellent secondary benefits.
Company Description
Merkle, a dentsu company, operates in 30+ countries with over 16,000 employees. In the Netherlands, more than 150 Merkle employees work with clients like ASML, Albert Heijn, HEMA, Carglass, and Signify. Merkle Netherlands is a strategic partner of Google, Adobe, Salesforce, and Selligent.