AMS DB March Meetup

Databricks kindly offered to host our third meetup - we hope you're all planning to join us at their Amsterdam office!

Agenda:
17:30 Doors open
18:00 Welcome
18:10 A deep dive into session memory management in PostgreSQL - Matthias van de Meent
18:40 The Missing Manual for MySQL Audit Plugins - Martin Alderete
19:10 Food & refreshments
19:30 Lessons learned on building a database from scratch (Nabia-DB) - León Castillejos
20:00 Lightning talks
20:15 Networking

Matthias is a PostgreSQL hacker at Databricks, through the acquisition of Neon, Inc.

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The Missing Manual for MySQL Audit Plugins - Martin Alderete
Developing a MySQL audit plugin often feels harder than it should. While the Audit API exists, there is very little guidance on how to build production ready plugins that are safe, observable, and performant under real production load.

This talk presents the “Missing Manual” for MySQL audit plugins, based on real-world experience designing lightweight, low-latency auditing solutions. Rather than getting lost in the weeds of the C++ source, we will build a clear mental model of the plugin's anatomy: how it integrates into the MySQL execution flow and the critical constraints every author must respect.

We will explore:
* The Lifecycle & Anatomy: From initialization to the event notification loop, understanding how a plugin integrates within the server.
* The Hot Path: Practical patterns for speed—early filtering, stack-based processing, and asynchronous, non-blocking offloading.
* Concurrency without Pain: How to handle MySQL’s multi-threaded environment while avoiding common synchronization pitfalls.
* Observability as a First-Class Citizen: Exposing internal state via native MySQL status variables for Prometheus/Grafana integration—without impacting query performance.

The session includes a demo of a functional, lightweight audit plugin. We will walk through its structure, load it into a running MySQL instance, and observe its behavior and metrics.

This session is aimed at engineers who want to design MySQL audit plugins that do their job without becoming a bottleneck, and who value pragmatic engineering over theoretical perfection.

Martin Alderete is a Principal Site Reliability Engineer at Booking with a strong background in distributed systems and system-level programming. He has experience in both academia—where he worked as a teaching assistant after earning his degree—and industry, leading teams building complex systems at scale.

He is passionate about open source and emerging technologies, and is an active contributor to multiple open-source projects and technical communities.

Before joining Booking.com, he worked across several industries, including space, where he served as a Satellite Reliability Engineer, building (and debugging) systems to operate satellite fleets.

He is based in Amsterdam and originally from Patagonia, Argentina.

Lessons learned on building a database from scratch (Nabia-DB) - León Castillejos
Databases are one of the most important Computer Science topics, but sadly they are not often explored in sufficient depth beyond comparisons of already existing implementations. Let's learn by doing: what are the fundamental building blocks of a database? How can we think strategically about storage, reliability, and distributed systems?

León Castillejos is a graduate in Computer Science & Engineering at Universidad Rey Juan Carlos. He has over ten years of experience in the industry and currently works at Booking.com as a Site Reliability Engineer II, at the intersection between large-scale bare-metal datacentres, cloud technologies, security, and networking.