---
title: "AI Developer"
description: "We build AI agents and automations for mid-market companies. As AI Developer you build AI applications in Python that go beyond a demo: LLM integrations, RAG systems and AI workflows, connected to the documents, databases and business applications our clients already use. You work in the build team led by the AI Lead."
canonical: "https://www.whatsnext-ai.com/careers/ai-developer"
datePosted: "2026-10-28"
location: "Rotterdam (hybrid)"
employmentType: "FULL_TIME"
---

# AI Developer

Engineering · Rotterdam (hybrid) · Full-time · 40 hours per week · Employed · €4,500 – €7,500 gross per month, plus 8% holiday allowance

We build AI agents and automations for mid-market companies. As AI Developer you build AI applications in Python that go beyond a demo: LLM integrations, RAG systems and AI workflows, connected to the documents, databases and business applications our clients already use. You work in the build team led by the AI Lead.

## Responsibilities

- Build AI applications in Python.
- Develop LLM integrations, RAG systems and AI workflows.
- Connect AI systems to APIs, databases, documents, email, CRMs or other business applications.
- Design and implement document processing, retrieval, embeddings, chunking and metadata structures.
- Work with structured outputs, function calling, tool calling and controlled workflow steps.
- Create automation workflows in n8n that integrate AI models, APIs and processes.
- Build human-in-the-loop processes in which a person checks what the AI does.
- Test and evaluate AI output for quality, reliability and usefulness.
- Debug AI systems that do not do what they should.
- Work with the AI Lead, consultants and other developers to turn client questions into working solutions.

## Requirements

- Experience as a software developer, backend developer, AI engineer or similar technical role.
- Strong experience with Python and bringing applications to production.
- Experience with LLMs and modern AI applications.
- Understanding of RAG, embeddings, vector databases, chunking and retrieval.
- Experience with APIs, databases and backend development.
- You can test, evaluate and improve AI output.
- You understand security, privacy and data handling.
- You can work with technical uncertainty and reach a practical MVP quickly.
- Good English and/or Dutch.
- HBO/WO working and thinking level.

## Nice to have

- Experience with frameworks and tools such as LangChain, LlamaIndex, Semantic Kernel, DSPy or similar.
- Experience with vector databases such as Qdrant, Weaviate, Pinecone, pgvector or Chroma.
- Experience with FastAPI, Docker, PostgreSQL, Supabase or cloud platforms such as GCP or AWS.
- Experience with tool calling, function calling, MCP or agent frameworks.
- Experience with document parsing, OCR, PDF extraction or multimodal AI.
- Experience with Azure OpenAI, Anthropic Claude, Google Gemini or open-source models.
- Experience with LangSmith or other observability and evaluation tooling for LLM systems.
- Experience building and maintaining CI/CD pipelines.
- Experience with frontend or full-stack development.

## What we offer

- €4,500 – €7,500 gross per month, plus 8% holiday allowance.
- A 40-hour work week.
- Hybrid working from Rotterdam or Lelystad.
- A laptop for your work.
- The latest AI tools and subscriptions, paid by the company.
- You take the AI trainings we give clients yourself.
- A budget for professional development.
- Travel allowance and reimbursement for business trips.
- Short lines and little meeting overhead.
- Team dinners and outings.
- The opportunity to grow with the team.

[Apply](mailto:hr@whatsnext.cc?subject=Application: AI Developer)