fidzu : django

(One of my summaries of the 2026 one-day PyGrunn conference in Groningen, NL).

When automating in a big company with many systems, you often end up with spaghetti: many systems connecting to a lot of the others... A common solution is to have a "bus architecture". Generic existing "enterprise service bus" solutions were clearly overkill, so he proposed an alternative solution.

He made a couple of assumptions/choices. All data is tabular data. He wanted to store a copy of data in a database. SQL views to access the data. So: multiple sources that he wanted to import in a central database (which would function as a sort of "read-only enterprise service bus"). And a generic sql/view-based way of accessing the data.

He initially focused on read-only data. And he started real simple. Just a bash script that ran regularly that scraped data from other systems and injected it in the database.

In the second version of the system, for every system he wrote a target/command in a Makefile. Every thing that needed to be scraped got its own table (called a "list" in his system"). Lists could be compared. The first killer app was a comparison between a telephone list and the list of employees so that differences could be consolidated.

For the third version, he started using more and more python. CSV file imports. Downloaders from REST APIs. All configurable so that he could use the same python script for many different sources.

He now had a simple sytem for which he could write views and exports.

• Publishing data on the intranet via the "jekyll" static site generator. For instance a "mug book" of all employees.
• And regularly exporting a list of names+emailaddresses in a format suitable for the multifunctional printer: to make it easy to select your email address when scanning on the printer.
• An export to a google spreadsheet that combined the holiday spreadsheet with the data on part-time days.

Security was handled with a role-based system.

Unrelated photo: the "lac de Kruth-Wildenstein" reservoir during a family holiday in France in 2006.

(One of my summaries of the 2026 one-day PyGrunn conference in Groningen, NL).

His parents owned a record store in some Dutch town. First records, then CDs. A social shop where you would gather to listen to CDs to determine whether to buy them. His father's brother actually started the oldest record store in Amsterdam, Concerto. It still exists.

Then the world changed. Napster, CD-burners. Illegal downloading. (He himself was one of them). His parents stopped selling music in 2008. He himself got into engineering. He ended up in South Africa, doing workflow orchesration for radio telescopes. There he introduced Docker and containers. He gave a talk at Pygrunn about it in 2016.

While he was in the South African desert, in Sweden someone started the Spotify company. He actually had used a library ("luigi") made by Spotify in his telescope work.

He tried to get a job at Spotify and succeeded. So the kid who grew up in a record store now works at the company that reinvented how people listen to music.

It all started for Spotify with Java (jboss 5). They hated it. It was replaced with Python: the reason was that nobody hated it. 80% of the code became python. A lot was async: they used "twisted" in the beginning, later gevent and greenlets.

But the Python GIL (global interpreter lock) made multi-core impossible. So you needed to use multiple processes, each with their own overhead. They also didn't like the lack of type safety: they have 100+ services. Some of those problems are partially solved now, but at the time the switched back to Java. Partially it was cultural: they could hire quite some Oracle employees that knew Java.

Python was still used a lot, just not for the core services. Nowadays, Python is used a lot for machine learning. They have 950 Python services, 470 libraries. 180000 Python files in 7500 repositories. 322x FastApi, 272x Streamlit repositories. And still lots of luigi. Luigi is the framework that inspired airflow: it has lots of starts on github, the most of all their open source repositories.

They now also started pedalboard, a nice Pythonic way of modifying audio (it is a wrapper around a c++ library). Also nice: https://backstage.spotify.com/ , a backend/portal for collecting all the developer-related data. Workflow statuses and so. (The backend is open source, the dashboard not).

At Spotify, the programmers are really encouraged to use agentic programming. He hasn't touched his editor in the last six months! It really changed his life. Initially he was a bit depressed: can someone who's less talented but with the same amount of tokens really do the same as me? But it is really a next level and he gets amazing productivity out of it. Having unlimited tokens helps.

It changes open source. Forking used to be a declaration of war. Nowadays it is a sign of popularity. You can fork something and have AI keep it up to date with minimal engineer effort. When the cost of maintaining your own fork approaches zero, what does that do with the economics of open source? Is cooperation still a thing? What is the goal/effect of open sourcing? Or is it only a way for AIs to find security bugs in your software?

His parents ran a record store for 42 years. Then technology disrupted the music industry. They had to reinvent themselves. It was scary and sad, but they adapted. Now the same force is disrupting our industry. Where will it go?

Unrelated photo: the "lac de Kruth-Wildenstein" reservoir during a family holiday in France in 2006.