Hi there, my name is Willem

I solve data problems.

Expert in SaaS development — from realtime dahsboards, predictive models and automations to full-stack solutions including SQL, Python backend, and iOS apps.

Expertise

Data Science

I like to craft end-to-end solutions. From model creation, to deployment and monitoring in production.

Things I make:
- Prediction models
- Tools using AI APIs such as ChatGPT
- Data cleaning and preprocessing pipelines
- Automated reports
- Automations based on data

Tools I use:
- Python
- Matplotlib
- Scikit learn
- Pytorch
- Pandas, Numpy
- APIs
- Machine learning
- Docker
- Github Actions
- Cloud instances

Data Analyst

I like to uncover hidden business insights from combining and analysing available data sources.

Things I make:
- Realtime dashboards
- KPI's and metrics
- One-off analysis
- Combined data sources
- Automatic triggers
- Data exploration to find trends

Tools I use:
- SQL
- Python
- Tableau
- Excel
- Glue code for combining data sources
- Custom implementations for live, realtime dashboarding

iOS Apps

I have fully designed, built and deployed multiple iOS apps, sometimes including a backend.

Things I make:
- User-friendly apps
- Basic app designs
- UX design
- UI Tests and End-To-End Tests
- Backend services

Tools I use:
- XCode
- Swift
- SwiftUI
- CoreData
- Figma

Employment

Data Scientist - Level.works

Aug 2022 - May 2023

Combined data from a MySQL database and a MongoDB database and transformed into a Redshift data warehouse using a star schema. This allowed us to easier answer questions such as "How have core metrics changed in a specific period?"
Automated a reporting process which used to take 3 people a full week to taking one person less than an hour. This involed combining Excel and MySQL data and creating custom PDFs.
Created dashboards that provide advanced analysis to help better decision-making in multiple departments such as marketing.

Data Scientist - Amber

Feb 2020 - Apr 2021

Created AVAA (Autonomous Vehicle Assignment Algorithm) using Python, Docker compose, Redis and MySQL. AVAA did over 50% of all vehicle planning so the 4 human planners could focus on unique cases such as car problems or complaints.
Introduced robust metric tracking in Tableau so my colleagues were aware of our progress

Data Analyst - ASML

Oct 2017 - Jul 2018

Automated updating of tens of thousands of master records in SAP using VBA. This saved my colleagues hundreds of hour every month and ensured we ordered parts at the lowest price, sometimes saving thousands of euros on a single part.
Did a comprehensive analysis to reduce the suppliers of small electronic components from dozens to just a few. This saved money, reduced complexity and reduced headaches.

Apps

Qept

Got something on your mind? Save it with Qept!

Genius can't be planned, great ideas strike at the most random times.

The goal of Qept is to be the fastest way to store your ideas and get on with your life.

Qept is currently under active development and is my 'main' app. I aspire to eventually make it cross-platform and add additional functionality to help you make the most of the ideas you already have.

Learn more

The Quickest Way To Take Notes

Over
4 000
Users

Remember Your
6 000
Daily Thoughts*

Featured On

Hire Me

Interested in collaborating with me?

I'm available as a freelancer!

I'm available on-site anywhere that's at most 1 hour away from Den Bosch, The Netherlands. I take remote/async assignments worldwide.

Feel free to contact me:
willemdebeijer [at] outlook [dot] com