Jilles van Gurp

Jilles van Gurp photo

CTO@FORMATION, consultant, Berlin Germany

Experienced tech entrepreneur, (interim) CTO, strategy, and consultant, hands-on troubleshooter and mentor.

  • Search Engines / ElasticSearch
  • Geospatial technologies
  • Entrepreneurship
  • Leading Remote Teams
  • Agile Team Management
  • Technical consulting
  • Team Workshops / Troubleshooting
  • Server-side cloud architectures

About Jilles

Dr. Jilles van Gurp is an accomplished technology leader with a strong track record of founding and running innovative startups and leading technology teams to create breakthrough products. With over two decades of deep expertise in search engines, geospatial technologies, and agile team management, he excels in crafting technical strategies and solving complex problems to drive product development and achieve long-term strategic value.

Currently, Jilles is the CTO, of FORMATION Gmbh in Berlin. Jilles is a serial founder, troubleshooter, and has decades of experience building innovative software services, leading tech teams, and creating breakthrough products. His professional experience includes Senior Researcher at Nokia Research in Finland, Principal Engineer at Nokia Maps in Berlin. He also is a Search Engine consultant that has worked with clients such as BCG DV, Soundcloud, Bertelsmann Group and others with their search challenges, product development, and roadmap.


  • Natural team player, with strong interpersonal skills, can build and lead agile teams, coach and mentor individuals at all professional levels and from a wide variety of backgrounds.
  • Loves to figure out technical roadmaps and tackle the difficult strategic questions with a focus on pragmatic early releases to achieve long-term strategic value.
  • Deep technical expertise and mindset, with hands-on approach to dealing with new domains, tech stacks and paradigms. Using Lucene, Solr, and Elasticsearch for 20 years.
  • Pragmatic problem solver and fan of lateral-&-end to end thinking, love to iterate!

Jilles holds a PhD in Software Engineering from the University of Groningen in the Netherlands (2003) where he also worked as a postdoc, a Swedish Licentiate degree from the Blekinge Institute of Technology (2001), and a master degree from the University of Utrecht 1999.

Available For

  • High-level or hands-on consulting on search architecture, vector search, & elasticsearch/opensearch.
  • Trainings and workshops** to skill up your team. A big part of consulting is mentoring, knowledge transfer, and coaching people around me. A lot of my clients are struggling to bootstrap their way to success with their search technology stack. I can help you make sense of it all and set your team up for success.
  • Improving the quality of your search ranking. I built Rankquest Studio to help my clients benchmark their search quality because I have found that a lot of them were struggling with a lack of a structured approach to evolving their search in a datadriven way.
  • Exploring the possibilities of vector search, retrieval augmented generation (RAG), and LLMs for your use case. This is a fast evolving field and there is quite a bit of low hanging fruit ready to pick. I can help you get started with this.
  • Architecture / ETL reviews, or hands-on deep dives.
  • Performance tuning your queries and mappings for faster performance and lower cost. A lot of my clients struggle with performance and cost issues. If you suspect you have performance issues that are costing you money, I can come in and do a quick analysis of your stack and provide you with recommendations.
  • Team troubleshooting & interim management & mentoring.
  • General consulting on tech, roadmap, or product.

Just to manage expectations, I generally work as a consultant, not as a freelance developer. This means I can work with you in short projects or on a retainer fee basis. While I am very hands-on technically, I’m not able to join teams fulltime as I’m focused on running my own company.

Feel free to reach out by email for setting up a short call on how I can help you.


I maintain several projects on Github that relate to my activities as a consultant and that we use at FORMATION as part of our product platform. Here is a small selection of things I’ve recently worked on:

  • rankquest-studio Rankquest Studio is a web based tool that you can use to benchmark search relevance metrics for your search APIs. You can try the latest version here.
  • kt-search Multi platform kotlin client for Elasticsearch & Opensearch with easily extendable Kotlin DSLs for queries, mappings, bulk, and more.
  • querylight Querylight is an in memory, kotlin multi platform text indexing library that implements tf/idf and a minimal query language. Great for client side search in web apps, android or other Kotlin apps.
  • geogeometry GeoGeometry is a set of algorithms and functions for manipulating geo hashes and geometric shapes with geo coordinates. We use this at FORMATION and this library has served me well in my various startups.
  • more


  • Email: jilles AT jillesvangurp.com
  • Cellphone: +49-176-6189-5701. I’m also on WhatsApp and Signal. Please coordinate asynchronously before calling. I prefer video calls.
  • Github
  • Linkedin
  • Twitter
  • Mastodon
  • Generally @jillesvangurp on anything I use. That handle, like my name, is globally unique.

This Web Site

On this web-site you may find an archive of my blog (including some recent efforts) and PDFs of my published work from my academic career (1998-2009).

Privacy & Cookies

This site currently has no cookies that need setting, I don’t use any analytics, and I’m not interested in invading your privacy. Current browsers are making tracking quite hard in any case. Also, I actually enjoy using such browsers myself for this reason. The web hosting that I use may collect some server logs of course. Beyond that, I’m not aware of any kind of tracking or privacy invading tools on this website.

If you are looking for a privacy policy, you just read it. If you enjoy the content, reach out on e.g. Twitter, LinkedIn, etc.