As a passionate software engineer and system architect with over 20 years of experience, I specialize in developing robust and secure code. My fascination with computers started at a young age - I can still recall sitting in front of my MSX 1 at twelve, programming it to print "Hello, Leon." Today, my focus lies in building services with a clear and specific purpose. In my spare time, I like to stay updated with the latest technology trends and engage in software and hardware projects that explore these advancements. Some of my projects can be found on my website.
Cm.com | PayPlaza 01-10-2020 — present
As a principal lead I guided and inspired the development teams to move towards a modern tech-stack. I work closely with the business to develop and maintain our payment gateway. In my daily job I work with several teams to explain, implement and getting the feature to production. This includes designing and implementing API's, working with OPS to improve the deployment process and to analyse potential issues on production.
Highlights
- Migrating a Monolithic service into smaller services with microservice architecture in mind
- Create and maintain new microservices with Kotlin and Quarkus
- Helping the company to move towards a more Agile mindset
- Improving the CI/CD pipelines for automated testing and creating artifacts
- Worked on migrating the core service tech-stack from java 7 to java 11
- Created a kubernetes setup to easily run the microservices on our local machines for easy development with RancherDesktop
- Maintained and enhanced the current portals for the Customer Care Services team
- Inspired the teams to look at new frameworks, as an example, a POC with FlyWay
IceMobile 01-08-2016 — 01-10-2020
Responsible for designing and improving the platform for all business needs and helping multiple development teams to bring clarity on the solutions. Contributed to building loyalty solutions for our international retailers, focusing on developing proper application services with Security, Performance and Monitoring in mind.
Highlights
- Introduced async services for better performance handling
- Changed from Monolithic Architecture to Service Oriented Architecture
- Laid the foundation for the migration of all our services from running Docker to the RedHat Openshift Platform
- Liaison with the business to translate the business needs into a concrete development plan
- Consul for Solution Architects and developers on creating the best design and solution for the platform (productize vs customize)
- Instigator for using ArchiMate as the main tool for documenting Architecture
- Set the standards for the NodeJS discipline by introducing guidelines for our services
- Worked on improving the CI/CD pipelines for automated deployments to our clusters worldwide
- Designed and set up new API's to improve our time to market
- Enhanced our monitoring and alerting on multiple services using Prometheus and Grafana
- Inspired the teams to look at new frameworks, as an example, a POC with GraphQL
IceMobile 01-07-2012 — 01-08-2016
Leading a small team of developers to build backend json/rest api services for mobile platforms. Also responsible for leading the migration of our infrastructure to Docker for quick and easy development and deployments.
Highlights
- Designed the second generation of the platform to be robust and scalable
- Built new services in NodeJS and PostgreSQL for data storage
- Initiated multiple Hackathons to have some fun, build cool stuff and share knowledge
- As a teamlead guiding and helping the backend developers to develop themselves, both professional and personal
- Migrated the platform to the cloud with AWS and Docker
- Ambassador for TDD and XP
- Building REST api's together with Frontend developers
- Working with Ansible to automate deployments
- Designing and building the database schema's
- Built a custom REST api proxy between a retailer service and mobile apps with NodeJS, ElasticSearch and MongoDB
- Built the first generation loyalty platform in Java with Mysql
Telfort / HP for the Telfort account 01-01-2008 — 01-07-2012
As part of the JAVA team I was responsible for all the backend services used for the order intake flows build in Java and for the internal systems to transport data from one system to another.
Highlights
- Teamlead for the Java backend development team
- Introduced SCRUM to the Java backend development team
- Creating high level design documents for the business and the development team
- Working closely with Operations for supporting on upgrading applications as Tomcat and Subversion
- Writing scripts to automate deployments
- Implementing CXF soap clients for internal services which are used by the java portals
- Creating CXF webservices for 3rd parties and internal provisioning software
- Built the consumers intake portal with Spring-webflow
- Introduced CXF and changed the Axis clients to use that framework
- Built a java application to push and retrieve billing information from sftp clients
- Created a Java application with Hibernate, Sitemesh and Displaytag for the status reporting
- Built a Perl application for encrypting emails which are received and sent from other providers
- Created the migration flow of a user with spring-security
Tiscali 01-06-2005 — 01-01-2008
As a Java application developer worked on services to implement business changes
Highlights
- Worked on an inventory service that could scan all tomcat instances for the services and versions and push the data to a single service (CMDB) for a nice overview for the OPS team
- Handling incoming 2nd line tickets
- Learned Java and Perl development
SQR 01-05-2000 — 01-06-2005
As part of the development team I was building and maintaining websites for big companies like Dela, Efteling and Texaco
Highlights
- Worked with css, html, php, MySQL and Javascript
- Built a cms based on mysql and php for easy changing content on websites
- Deploying and maintaining Solaris and Linux systems for customers
- Setup and maintain email services
Capgemini Academy 03-09-2019 — 06-09-2019
Het effectieve werken BV 01-02-2019 — 04-02-2019
Flow IT BV 03-06-2018 — 04-06-2018
M.T.S. Elektrotechniek Spaklerweg 01-01-1996 — 01-01-2000
O.S.B. 01-01-1991 — 01-01-1996
Self study —
Server OS
- Debian
- Ubuntu
- SmartOS
- OpenSolaris
Virtualization
- AWS
- Azure
- Docker
- Kubernetes
Databases
- MySQL/MariaDB
- PostgreSQL
- MongoDB
- Redis
Messaging
- Redis
- RabitMQ
- SQS
- SNS
IDE's
- IntelliJ
- Visual Studio Code
- VIM
Automation
- Bash
- Zsh
- Ansible
- Terraform
Javascript
- NodeJS
- NPM
- Restify
- Mocha
- Knex
- JSON
Java
- Kotlin
- Quarkus
- Panache
- TestContainers
- Java
- Spring framework
- Hibernate
- SQL
- Maven/Gradle
- JUnit
Monitoring
- Prometheus
- Grafana
- ELK Stack
Sports
- Triathlon
- Cycling
- Running
- Swimming
Hobbies
- Gaming
- Nerding
- Coding
- SimRacing
- Investigating new technologies like LLM, OpenAI, Ktor and more :)