Over the summer, I was thinking about my role in the Graph Data Council (GDC, formerly known as the Linked Data Benchmark Council, LDBC). I became a technical contributor to the GDC in early 2017 and, over the years, I joined its board of directors and helped overhaul the organization’s structure, finances, and IT infrastructure. As part of my research, I worked on the GDC’s benchmarks, reworked its auditing guidelines, and supervised more than a dozen database audits....
🤖 Below is an AI-generated summary of my FOSDEM 2025 talk (based on the slide deck). What are graph databases really about? At their core, graph databases are about joins. Despite marketing claims from some vendors that relational databases “cannot join,” the reality is more nuanced. Relational systems handle joins perfectly well at the execution level. What graph databases actually bring to the table is syntax sugar and specialized optimizations for join-heavy workloads....
Recently I was helping a family member setting up a Revolut account in Hungary. A step in this process included verifying their address. It seems to me that – unlike many fintech apps – Revolut does not accept utility statements or bank statements, but instead requires you to upload a picture of your residential address card (in Hungarian: “lakcímkártya”, or “lakcímet igazoló hatósági igazolvány”). The residential address card is one of the pinnacles of Hungarian bureaucracy – it is both quite pointless and also very important, you often cannot get things done without having it with you....
Since the acquisition of Kùzu, a number of forks have popped up: LadybugDB/ladybug: Ladybug is an embedded graph database built for query speed and scalability. predictable-labs/ryugraph: Ryu, a fork of Kuzu, is an Embedded Property Graph Database built for speed with vector search and full-text search built in. Kineviz/bighorn: Integrates with Kineviz’s GraphXR visualization platform. Supports both embedded and stand-alone server modes. Vela-Engineering/kuzu: KuzuDB fork maintained by Vela Partners. Embedded graph database for AI agent memory with concurrent multi-writer support....
This tutorial is an adaptation of “Public DuckLake on Object Storage” to the object storage of Leafcloud, an Amsterdam-based cloud provider. Hosting DuckLake on Leafcloud Setting Up the Object Store Navigate to the Leafcloud dashboard at https://create.leaf.cloud/. Go to Object Store | Containers and create a new container. We’ll use the name ducklake-storage. Tick the checkbox for Public Access and copy the link. This will be e.g. the following: https://leafcloud.store/swift/v1/AUTH_f84982a3c5d04bd0846197d8e8ce3ddd/ducklake-storage Setting Up the OpenStackClient Fetch the credentials from Leafcloud....
(Updated on 27 June 2026 to reflect my latest experience.) Installing Windows 11 on the Framework Laptop 13 turned out to be trickier than I initially envisioned. The main difficulty was that the Windows 11 image does not recognize the disk manager of the laptop’s motherboard. So, without installing that driver first, it was not able to create the partitions required for installation. Configuring the boot During boot, press F2 and pick Administer Secure Boot....
“Benchmarking gone wrong”, one of the best and funniest benchmark talks I’ve ever come across – it’s well worth 6 minutes to watch it....
This year I have taken a few long train rides across Europe, such as Berlin to Amsterdam. I found that these need a bit more preparation than the typical short flights within Europe, so here’s a(n incomplete) checklist for these trips: Gear: Dress comfortably. Take noise cancelling headphones. Take multiple charging cables. Some companies just rolled out USB-A ports, so I would definitely take both a USB-A and a USB-C cable for phones....
Following the recent retirement of KùzuDB, I published an updated version of my Graph Databases slide deck. I originally presented this back in February at FOSDEM 2025. Now I updated it with new systems such as KùzuDB’s fork, LadybugDB....
In the last decade, I had my fair share of bad sleep. Often, I pushed through it helpless and the usual tips – aim for a regular bedtime, stop caffeine intake mid-afternoon, reduce screen time in the evening – did not help much. However, over the years I built up a repertoire of techniques. This is obviously not medical advice. All I can say that if you’re struggling with bad sleep, I encourage you to experiment....