ML Engineer · Amsterdam
Wouter Wijffels
I build ML systems that run in production — churn models deployed across 5 countries, LLM pipelines processing a million+ interactions, monitoring infrastructure that catches problems before they become incidents. Most of my time goes into the boring-but-hard parts: data contracts, multi-market deployment, keeping models honest over time.
Projects
View timeline →LLM Summarization & Classification
Near real-time pipeline on AWS Bedrock: conversations ingested → PII masked → summarized and classified → auto-filed in CRM. 1.3M interactions per year.
International Churn Model Deployment
Single XGBoost model deployed to 5 countries via S3 distribution. Each country has its own data warehouse and marketing automation — all read from the same prediction store.
MLOps Monitoring Platform
Centralized observability for 15 models and 400+ pipelines. Drift detection uses statistical process control — not threshold alerts — which cuts false positives significantly.
Content Personalization Engine
LLM reads marketing automation group selections and generates personalized campaign prompts per segment. Pilot running.
A/B Test Uplift Prediction
Predicts expected uplift per segment before a campaign launches, using historical experiment data. Replaced intuition-based targeting with model-driven decisions.
Semantic Search for Procurement
Hierarchical item clustering with supplier price comparison. Drag in a price offer PDF and instantly find comparable products from other suppliers.
Procurement Analytics
Margin tracking per supplier, product, and category against webscraped competitor prices. Built when Picnic left its buying cooperative and started negotiating directly.
Supply Forecasting System
Hybrid time series + regression forecasting for brewery supply. COVID-19 signals from Our World in Data used as regression features. Confidence intervals fed into stochastic allocation.
Commodity & Gas Index Mapping
NLP mapping of public gas and commodity indices to supplier cost structures — built to verify whether supplier price increase claims during the Ukraine war were justified.
Email Scraper — 3PL Stock Updates
One-button local app that parses HTML stock update emails from the logistics partner and outputs structured Excel files per warehouse. Rolled out to 4 country operations teams.
Stack
Background
MSc Transport, Infrastructure & Logistics — Cum Laude
Delft University of Technology
BSc Industrial Engineering & Management
University of Groningen
Started with operations research and logistics optimisation, moved into data science when the tooling caught up with the problems. Most of my work since has been on the gap between a working notebook and a model that reliably serves predictions in production — deployment patterns, monitoring, multi-country infrastructure.