I’m a software developer and technology leader with over 20 years of experience in software development for data processing at scale and conceptual data modelling. Programming-wise, I am most fluent in Ruby and Java, with a smattering of Python, Kotlin, Golang, and Typescript. I have a background in Artificial Intelligence, semantics, linked data and ontologies. I live and work in Wellington, New Zealand.
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Projects
Eclipse RDF4J
Founder & Primary Developer • 2003 — 2021Eclipse RDF4J is a powerful Java framework for processing and handling RDF data. This includes creating, parsing, scalable storage, reasoning and querying with RDF and Linked Data. It allows you to connect with SPARQL endpoints and create applications that leverage the power of linked data and Semantic Web.
The project grew out of research during my PhD project and was originally co-developed by myself and Arjohn Kampman.
W3C SPARQL Working Group
invited expert / WG member • 2003 — 2007The W3C Data Access Working Group (DAWG), later renamed SPARQL Working Group, focused on producing a set of standards for querying and manipulating data in the RDF data model. This became SPARQL - the "Simple Protocol and RDF Query Language". During my tenure as invited expert and later member of the working group, I contributed to several W3C Recommendations, including the SPARQL query language itself, as well as the Protocol standard, and the SPARQL XML results format.
Work Experience
Culture Amp
Engineering Team Lead • Sept, 2022 — PresentLeading a multidisplinary team responsible for scalable data ingestion, processing and enrichment in the Culture Amp platform.
- Led the technical design and optimization of core systems for the Employee Data platform, ensuring high performance and scalability for critical data processing and API delivery.
- Delivered high-impact solutions including employee data ECST topics in Apache Kafka and a robust REST API, which serve as foundational components for external integrations and internal applications.
- Architected and implemented solutions that scaled data distribution, preparing the platform for rapid growth and increasing data volumes.
- Ensured production quality and reliability of delivered features through rigorous design, testing, and adherence to engineering best practices.
- Drove continuous improvement initiatives, leading to enhanced stability and throughput of product delivery.
- Led architectural decisions for high-impact initiatives, preparing platform for growth and scaling through strategic adoption of Apache Kafka for data distribution.
- Collaborated closely with Team Lead, Product Management, Design, and other stakeholders to translate business requirements into technical execution plans for key product features.
metaphacts GmbH
Principal Software Engineer • Feb, 2020 — May, 2021Provided technical leadership by setting technical roadmaps and architectural guidelines for the metaphactory Knowledge Graph platform, with a focus on delivering customer-centric 'low-code' solutions.
Culture Amp
Senior Machine Learning Engineer • Nov, 2018 — Jan, 2020Co-led establishment of a machine learning practice. Developed scalable solutions for processing inspirations and actions, and improving support for HR/team managers, enhancing their ability to act on survey results.
Billcap
Senior Software Engineer • Feb, 2017 — Oct, 2018Senior designer and developer for an innovative SaaS platform for energy retail operations, leveraging Ruby on Rails within the AWS ElasticBeanstalk cloud environment to deliver enterprise-grade solutions.
InsightNG
Chief Technologist / Co-Founder • Jan, 2012 — Aug, 2016Co-founded and served as chief engineer, defining the overall architecture and leading R&D for a new visual knowledge discovery platform, integrating machine learning and advanced knowledge representation.
Wageningen University - Food & Biobased Research
Senior Developer/Researcher • Aug, 2007 — Dec, 2011- Designed and developed innovative software solutions in both Java and Microsoft C# .Net for various customer projects.
- Led a cross-functional team in developing a research management system for a large research institute in the food sciences.
- Provided leadership on object-oriented principles and software design.
- introduced Agile principles (e.g. sprint planning and test-driven development) and supporting tools (Eclipse, Subversion, JIRA/Greenhopper) to the team.
Eindhoven University of Technology
Lecturer/Researcher - Architecture of Information Systems Group • Sept, 2005 — Jul, 2007- Researched the application of semantic web technologies to web-based information systems and adaptive hypermedia, and developed proof-of-concept software in this area.
- Taught undergraduate courses on web-based information systems and on relational databases.
- Coached Master and PhD students for their final thesis.
Education
PhD - Artificial Intelligence • 2005
VU University AmsterdamThesis: "Storage, Querying and Inferencing for Semantic Web languages"
Advisor: prof. dr. Frank van Harmelen