Curriculum Vitae


  • Age: 41
  • Location: Arnhem
  • Email:

Working Experiences

Company TenneT TSO
Job Title Kubernetes Engineer
Period May 2022 - May 2024

As part of the Platform-as-a-Service team, I was responsible for developing and maintaining the Kubernetes platform TenneT deploys for Mission-Critical deployments. One of the biggest milestones was onboarding the PMS application, some people called it the biggest IT change TenneT had seen in the last 20 years. This mission-critical application is used in the Control Room to monitor the flow and distribution in the power grid.

Some of the major changes and improvements I was part of:

  • Removing redundant or unnecessary cluster settings which could be determined logically
  • Removing Helm application deployments from terraform and deploying them using ArgoCD
  • Adopting DHCP for cluster deployments
  • Making use of Rancher nodepool functionality instead of creating and maintaining virtual machines with terraform
  • Using Portworx clouddrives instead of terraform-managed disks for virtual machines
  • Implementing mature version update promotions within clusters using ArgoCD (following GitOps-at-scale guidelines)
Company Ultimaker
Job Title DevOps/Cloud Engineer
Period July 2021 - May 2022

Continuing my work for Ultimaker in the Cloud. Development is going fast, userbase grows quickly and requirements are changing. We made it a point to try and simplify the architecture. This culminated in a project targeted at deploying all applications using Google Cloud Run instead of Kubernetes clusters. This not only simplifies the architecture but simultaneously reduces costs and eases deployments and rollbacks.

  • Enable better concurrent connection handling in applications
  • Migrate Kubernetes deployments to Cloud Run
  • Move secrets from Hashicorp Vault to Google Secrets Manager
  • Eliminate use of Google Service Account credential keys, use Workload Identity instead
  • Implement ArgoCD Deployments on Kubernetes
  • Created a Virtual printer to enable easy QA / testing
  • Create a GitHub integration for more user-friendly Lab Environments
Company RAMLAB
Job Title DevOps/Linux Engineer
Period February 2021 - July 2021

RAMLAB created a system to utilize a welding robot to 3D print metal parts on demand. Cool stuff. The hardware needed to support this, is powered by inhouse developed software.

My job as a Linux Engineer was to enable RAMLAB to automatically roll out these new hardware systems with as little human interaction as possible. We achieved this by utilizing MAAS (Ubuntu server deployments), Ansible (AWX), SSH authentication, JIRA Asset Management and some Google Cloud resources. By connecting all the API’s we were able to automate installations from beginning to end.

  • Configured automatic Ubuntu server deployments with encrypted disks, RAID config and SSH server during boot for troubleshooting
  • Used Hashicorp Vault for centralized SSH key management and certificate signing
  • JIRA Asset Management for centralization of customer configuration, syncing data to MAAS and Vault among others
  • AWX for rolling out deployments and updates for live systems
  • WireGuard VPN security
  • Dockerized a Windows client tool, removing the need for a 24/7 Windows Server running
  • SecureBoot enabling servers with custom Linux kernels
  • Using Terraform to manage all the infrastructure parts, setting up AWX and Vault
  • Created a custom ssh tool which looks up customer information, generates a temporary SSH keypair, has it signed by Vault and connects over the VPN to the right machine
Company Ultimaker
Job Title DevOps/Cloud Engineer
Period February 2019 - January 2021

Ultimaker creates the best 3D-printers in the world. These printers are manageable through the cloud, enable you to monitor, start, stop and duplicate print jobs and much more, from anywhere. As a Cloud Engineer my main job was to help Ultimaker bring their Cloud Infrastructure to a higher standard.

  • Described entire Google Cloud Platform infrastructure in Terraform code
  • Seperated Kubernetes configuration from application code
  • Created a uniform building / testing / deploying workflow for all applications
  • Created and implemented a custom Helm chart for deploying applications on Kubernetes
  • Migrated local MongoDB databases to MongoDB Atlas
  • Applied several security / availability improvements (like spanning GKE clusters over several zones)
  • Implemented the Istio Service Mesh
  • Deploy applications using GitOps (Weaveworks)
  • Created testing/lab environments for applications using Google Cloud Run
  • Improved Docker builds with caching / stages and BuildKit
Company Avisi
Job Title Linux DevOps Engineer
Period February 2018 - February 2019

In Februari I returned to Avisi, in their beautiful new office building to continue my work for the Atlassian Products & Services team as a Linux DevOps Engineer.

  • Updated the AWS Infrastructure:
    • Make use of Auto Scaling Groups
    • Modify the Ansible playbooks to automatically create new AMIs
    • Make use of EFS for shared data

In October 2018 I joined the platform team and helped develop their new infrastructure on the AWS platform:

  • Used Terraform, Consul and Nomad to deploy Docker containers
  • Created Docker images for most of the Atlassian applications: Jira, Confluence, Bitbucket and Bamboo.
  • Also created Docker images for SonarQube and Artifactory
  • Updated the infrastructure code to make use of Application and Network Load Balancers instead of the Classic Load Balancers.
Company Avisi
Job Title Linux DevOps Engineer
Period April 2017 - December 2017

I returned to Avisi to further support the Hosted Insight platform which was now beginning to gain quite some traction. With the insights gained from the experience of adding new customers to the platform, a number of features were added to the wishlist and it was my responsibility to implement them.

  • Hosted Insight platform support/development:
    • Added host-based/path-based routing for customers
    • Switched backup solution to Restic.
    • Migrate various customers to the platform
    • Use PostgreSQL WAL archiving method instead of SQL dumpfiles for backups
    • Upgrade all customers’ Atlassian applications

In October I switched teams to APS - Atlassian Products & Services, where I supported the Atlassian Experts:

  • Migrating data from a large MediaWiki instance (2000+ users) to Confluence
  • Imported existing AWS hosting environments into Terraform
    • Modularized for different (production, testing) environments
    • Configuration of Application Load Balancers
    • Various EC2 instance types
    • Full networking configuration
    • Bastion host
    • Security groups
  • I wrote various Python tools:
    • Convert Atlassian Cloud Tempo worklogs to JIRA Server worklogs
    • Migrate Atlassian Cloud usernames to local JIRA Server accounts
    • Fix timezone differences in PostgreSQL databases
    • Fix hyperlinks from one Confluence base url to the other
Company IJsvogel Retail
Job Title DevOps Architect Online
Period January 2017 - May 2017

As DevOps Architect Online, I supported a number of teams in the IJsvogel Retail organisation, the corporation behind Pets Place and Boerenbond.

  • Responsible for day-to-day operations revolving around the e-commerce platform
    • Built on Magento 2
    • Troubleshooting issues and reporting them to the appropiate suppliers (payment providers, Magento 2 developers, iOS/Android developers)
    • Helped launching the Customers Loyalty program consisting of iOS and Android mobile apps
    • Together with the Online Business team I was responsible for Scrum sprint planning and project prioritization.
Company Avisi
Job Title Linux DevOps Engineer
Period June 2016 - December 2016

As a DevOps engineer, I was tasked to setup a new fully automated platform. Customers will be able to request a dedicated, Atlassian-stack based DTAP environment in a private cloud. Other tools like Jenkins and Rundeck may be added to the stack.

  • Set up Hosted Insight platform
    • Create and maintain Puppet code for shared services: puppetmasters, smtp services, DNS, nginx proxies, backup services etc.
    • Quickly and automatically deploy virtual machines for running Atlassian applications using a self-written Python tool
    • The backup- and restore process is completely automatic
    • Create and maintain documentation for the platform

Other software used:

  • Vagrant
  • PostgreSQL
  • OpenDJ (LDAP server)
Company Exonet bv
Job Title System Engineer
Period May 2015 - June 2016

There was already a lot of Ansible knowledge present at Exonet when I started working there. However, it was only being utilized to install specific software on servers once. I helped deploy Ansible Tower. At the time of writing Tower was being used to apply configurations to more than 150 servers every day. These configurations consist of self-written ‘roles’ aswell as the playbooks themselves. I deployed many different server setups, all using ansible playbooks, such as:

  • Magento setup:
    • This setup hosts Magento-based CMS sites.
    • Nginx is optimized with Magento-specific settings.
    • It uses NFS shared storage on a NetApp cluster.
    • Backups are made amongst others with Bacula.
    • PHP is running in php-fpm mode.
    • There is a Redis instance per website for caching.
  • Trytond setup:
    • This setup uses nginx with gunicorn as backends.
    • PostgreSQL is used as a databasebackend and Sphinx / searchd for the search functionalities.
    • Python Trytond is installed into a virtualenv.
    • Redis is used as a caching backend.
    • Every service is controlled with systemd templates.
  • Plone CMS setup:
    • This setup is load-balanced using HAProxy on a number of Zope workers and Zope database hosts.
    • Each worker runs Varnish with a number of backends for each site. These are all periodically probed and removed from the pool if they are no longer responding.
    • The customer requested ansible playbooks on one of the worker to easily deploy and update sites.
  • Docker setup:
    • This customer uses docker extensively for deploying and automatically scaling websites.
    • Containers are limited to customer-specific networks.
    • Docker networks and nginx are managed with Ansible.
  • ElasticSearch / MongoDB / PostgreSQL / RabbitMQ / Redis cluster:
    • This setup contains a number of database servers and worker servers.
    • All services are running in either cluster mode or master/slave mode.
    • Workers run apps, written in go, that are exposed to the internet via nginx.

Besides engineering new setups and clusters, customers often requested a way of testing their software on their servers, without using the “live” servers. I used Packer to create Vagrant boxes that are identical to their production servers.

I also wrote a number of tools in Python:

  • server_check: This open source tool checks if a DirectAdmin server is still functioning correctly.
  • GitHub webhook: this webhook receives GitHub payloads, if certain criteria are met it will instruct Ansible Tower to start a new job.
  • Migration scripts: collect data, write it to JSON format, and read the data to call the DirectAdmin API to create new accounts, email addresses, transfer data, etc.
  • Ansible notification callback plugin (email).

Other duties include customer contact via phone and e-mail (3rd line support), configuring Cisco / NetApp infrastructure, implement firewalling and VPN using Juniper and pfSense appliances and implementing two-factor authentication for SSH.

Company Totaalnet Internet Works
Job Title Manager Engineering
Period November 2005 - May 2015

My job at TIW was two-fold: I was a Linux Engineer but also Manager of the department. As Linux engineer, my job mainly consisted of the following:

  • Managing 200+ web, mail, dns and database servers for the Shared Hosting platforms.
  • Implementing Puppet, DNSSEC, IPv6.
  • I created an Asterisk VoIP telephony system.
  • Migrated many servers from DirectAdmin, Ensim, cPanel etc to our own Control Panel.
  • Managing the network (BGP peerings and transits, IPv6 and uplinks).
  • Connecting our network to the AMS-IX and NL-IX.
  • Automatically creating VMWare virtual machines by implementing the C# API.
  • Engineering and developing the new Shared Hosting platform.
  • Developing systems administration scripts and services in Python, C# and Perl.
  • Developing and maintaining the Hosting and Domain names Control Panel for customers.
  • Third line support.

As Manager Engineering, I was responsible for the following:

  • Implement project management using Kanban/Scrum.
  • Lead the Engineering team (“Scrum” master).
  • Have periodic performance meetings with team members.
  • Ensure the company policies were applied and kept to.
  • Ensure the departmental planning were in line with corporate strategies.
  • Create and monitor budgets.
  • Measure and report on results of the department.
  • Describe, implement and ensure departemental processes.
Company Rockingstone IT
Job Title System Engineer
Period March 2002 - October 2005

At Rockingstone IT I was responsible for:

  • Installing and maintaining the company servers
  • Registering domain names for customers
  • Administrating user, e-mail and FTP accounts
  • Managing the company network
  • Developing various websites in Perl and PHP.
Company Radix ICT
Job Title System Engineer
Period December 2001 - March 2002

My job at Radix ICT was mainting and managing SCO UnixWare 7 servers on location at customers.

Company Landis ICT Group
Job Title Junior Support Engineer
Period June 2001 - December 2001

My job at Landis ICT Group was certifying for several SCO Unix courses with the intent on becoming a consultant.

Company BV
Job Title Server Administrator
Period January 1999 - June 2001

At I installed and was responsible for the servers that kept the site running.

Certifications and courses

  • 2023: Codefresh: GitOps at Scale
  • 2023: Codefresh: GitOps Fundamentals
  • 2022: CKAD: Certified Kubernetes Application Developer
  • 2022: HashiCorp Certified: Terraform Associate (002)
  • 2019: Certified Kubernetes Administrator (CKA)
  • 2016: Amazon Web Services - Certified Solutions Architect - Associate
  • 2014: VMWare VCP 550
  • 2007: RIPE LIR Training Course
  • 2006: NL-ix BGP4 Course
  • 2001: SCO UnixWare 7 CUSA
  • 2001: SCO UnixWare 7 ACE (Shell Programming)
  • 2001: SCO UnixWare 7 Master ACE


Amazon Web Services

  • EC2
  • Application / Network Load Balancers
  • Lambda
  • Security Groups
  • Auto Scaling Groups
  • Creating custom AMIs
  • EFS
  • EBS
  • S3
  • RDS

Linux / Unix

  • Ubuntu
  • Debian
  • Slackware
  • RedHat / Fedora Core
  • Gentoo
  • CentOS
  • FreeBSD, OpenBSD, NetBSD

Virtual Infrastructure

  • VMWare
  • Xen / XenServer
  • KVM

Configuration Management

  • Ansible
  • Puppet
  • Terraform

Continuous Integration & Deployment

  • Jenkins
  • Atlassian Bitbucket / Bamboo / Confluence / Jira
  • Docker
  • Vagrant / packer


  • MySQL
  • PostgreSQL
  • ElasticSearch
  • MongoDB
  • Redis
  • Memcache
  • SOLR


  • Python
  • Perl
  • PHP
  • C#
  • Java
  • Objective-C
  • Bash
  • Ruby

Server Technologies

  • Apache
  • nginx
  • Varnish
  • HAProxy
  • Supervisor
  • LogStash
  • Kibana
  • NodeJS / PM2
  • RabbitMQ

Backup Technologies

  • Veeam
  • R1Soft / CDP
  • Bacula
  • Rsync / rdiff
  • Restic