I am the Head of Developer Relations at DuckLabs, working on advocacy for the DuckDB, DuckLake, and Quack projects. I work on the documentation and the engineering blog and give talks. I run the DuckCon conference series and conduct interesting benchmark experiments.

Previously, I spent a decade in academia. I obtained my PhD in software engineering at the Critical Systems Research Group of TU Budapest, followed by a 3-year stint as a post-doctoral researcher at the Database Architectures group of CWI Amsterdam. My research focused on graph queries and graph analytics, and contributed to the benchmarks of the Graph Data Council (GDC, formerly known as LDBC). GDC is a nonprofit that promotes the use of graph data management technology and defines TPC-style graph database benchmarks. Between 2017 and 2026, I was an active contributor and later a board member of the GDC.

Along with updates on what I’ve been up to, I also share some notes on this site.

Links

GitHub – Twitter – LinkedIn – Stack Overflow – Google Scholar – DBLP

News

Sep: After almost a decade of being a contributor, I stepped back from the Graph Data Council to focus on my work around the DuckDB project.
Sep: I attended VLDB in Boston and organized two co-located events: the DuckDB Boston Meetup and the 21st GDC Technical User Community meeting.
Aug: DuckLabs announced that it joins AWS from September. The projects remain open source. Read the announcement post.
Jun: I organized DuckCon #7 in Amsterdam, the community conference around DuckDB, DuckLake, and Quack.
May: I gave a talk titled “DuckDB: Not Quack Science” at Ubuntu Summit 2026 (slides).
May: I led the rebranding of DuckDB Labs to DuckLabs. The new brand serves as the company behind the DuckStack: DuckDB, DuckLake, and Quack.
May: I was in charge of the launch and announcement of DuckDB’s new Quack protocol.
Apr: I gave back-to-back talks at Webkonf in Budapest and at PyCon Austria in Eisenstadt on DuckDB and DuckLake. For PyCon AUT, see my slide deck “Why would you import duckdb in your Python project?”.
Apr: I led the announcement of the DuckLake v1.0 lakehouse format.
Mar: I published “Big Data” experiments on the new MacBook Neo.
Feb: At FOSDEM 2026, I participated in the panel on OSS Funding and gave a talk “Database benchmarks: Lessons learned from running a benchmark standard organization” in the Software Performance Developer Room.
Jan: I co-organized the first DuckDB Developer Meeting in Amsterdam.

For older items, see the news archive.

Talks

Benchmark Organizations (FOSDEM 2026)

slide deck

DuckDB (GOTO Amsterdam 2024)

slide deck

Notes

Stepping back from GDC

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....

Graph databases after 15 years – Where are they headed?

🤖 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....

Verifying residential address for Revolut in Hungary

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....

Kùzu forks

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....

DuckLake on Leafcloud

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....

Installing Windows 11 on the Framework Laptop 13

(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....

Benchmark lightning talk

“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....

Preparing for long train rides

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....

Updated graph databases slide deck

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....

Sleeping tricks

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....

Links#

News#

Talks#

Benchmark Organizations (FOSDEM 2026)#

DuckDB (GOTO Amsterdam 2024)#

Notes#